0:00:00 > 0:00:06This programme contains some strong language and scenes viewers may find disturbing.
0:00:06 > 0:00:09Forensic science is at the forefront of every major criminal investigation in the UK.
0:00:09 > 0:00:12Detective work and science in general are very much the same.
0:00:12 > 0:00:17With exclusive access to a scenes of crime unit,
0:00:17 > 0:00:19our cameras go behind the police tape.
0:00:19 > 0:00:24The reason that forensic science is so powerful is that it's almost impossible
0:00:24 > 0:00:26to argue with what we've got.
0:00:26 > 0:00:31We follow the trail of evidence as the forensic experts piece together the hidden puzzle,
0:00:31 > 0:00:35unlock the secrets of the crime, and get inside the minds of criminals.
0:00:35 > 0:00:39Where we're standing now is where the shot's gone in from.
0:00:39 > 0:00:43We see how science and detective work come together.
0:00:43 > 0:00:47Our victim got a good beating in here, and was lucky he didn't die.
0:00:47 > 0:00:50To bring the guilty to justice.
0:00:50 > 0:00:52'Move forward, please, move forward.'
0:01:04 > 0:01:05PHONE RINGS
0:01:05 > 0:01:08'Police, emergency. What's happened?'
0:01:08 > 0:01:12'Someone's shot the front and back of my house with a gun.'
0:01:12 > 0:01:15'Right, OK, when did that happen?'
0:01:15 > 0:01:18'Just now, literally a couple of seconds ago.'
0:01:18 > 0:01:22'And explain to me why you think it was a gun. What's actually happened?'
0:01:22 > 0:01:26'Well, there's a big blast hole through my front door, might be one to look at(!)'
0:01:26 > 0:01:31'OK, and you think it was the front and the back of your house?'
0:01:31 > 0:01:36'Yeah, the front door is completely obliterated. Fucking bastards.
0:01:36 > 0:01:40'I've got two children in the house, do you know what I mean?
0:01:40 > 0:01:43'This is fucking ridiculous. It ain't got nothing to do with us.'
0:01:43 > 0:01:45- 'Are you OK?'- 'Yeah.
0:01:45 > 0:01:49I'm not to touch anything, am I? Just leave it exactly how it is, yeah?'
0:01:49 > 0:01:53- 'No, just leave it as it is.' - 'OK.'- 'OK.'
0:01:53 > 0:01:56Within minutes of the call being made, police arrive at the house.
0:01:56 > 0:01:59They're closely followed by officers
0:01:59 > 0:02:05from the Bedfordshire and Hertfordshire Scientific services unit.
0:02:05 > 0:02:09It's around about quarter past six on Saturday morning,
0:02:09 > 0:02:12and I've been called out to reports
0:02:12 > 0:02:16that someone's shot into someone's house,
0:02:16 > 0:02:19so I'm here, in Luton, at this hour in the morning.
0:02:19 > 0:02:21Let's see what we've got.
0:02:22 > 0:02:25Just getting protective clothing on,
0:02:25 > 0:02:30largely so that we don't take any of our fibres or any bits of evidence
0:02:30 > 0:02:33that we've picked up at other crime scenes into this crime scene.
0:02:35 > 0:02:41This is the fourth shooting in Luton that Mark and his team have had to investigate in the last two months.
0:02:41 > 0:02:45You can see in the front door of the house, there's a very large hole.
0:02:45 > 0:02:49It's consistent with someone having shot a shotgun into that house.
0:02:49 > 0:02:51We're thinking about what sort of parts
0:02:51 > 0:02:55would have been left behind from firing that shot.
0:02:55 > 0:02:57Shotguns are unique amongst weapons
0:02:57 > 0:03:01because when fired, they leave distinctive clues behind.
0:03:01 > 0:03:05This is the sort of damage I'd expect to see from a shotgun
0:03:05 > 0:03:10that's been fired, probably from around about the pavement,
0:03:10 > 0:03:11thereabouts.
0:03:11 > 0:03:15Basically, what you have is a column of pellets
0:03:15 > 0:03:19that's exiting the barrel of the gun, roughly the size and shape of my finger.
0:03:19 > 0:03:24All it would have needed is someone to be stood behind or walking past the front door
0:03:24 > 0:03:29at the time the shot went in, and they would have got almost all of the shot from that shotgun cartridge,
0:03:29 > 0:03:32plus bits of the door flying as shrapnel, you know...
0:03:32 > 0:03:35So yeah, someone could have died here.
0:03:40 > 0:03:44When the shot exits the gun barrel, it begins to scatter.
0:03:45 > 0:03:50The further away from the target, the wider the scatter of pellets.
0:03:53 > 0:03:56Looking closely at the hole in the door,
0:03:56 > 0:03:59there is more of an angle to the shot than we'd first seen,
0:03:59 > 0:04:04so it is possible that we've actually got someone shooting from over here.
0:04:07 > 0:04:12With an idea of where the gunman may have been standing in the attack,
0:04:12 > 0:04:16Mark goes on to comb the muddy ground in search of footprints.
0:04:16 > 0:04:18Over here, we've got...
0:04:20 > 0:04:21..a footwear pattern.
0:04:21 > 0:04:26So we'll capture that, as it's got some potential to be
0:04:26 > 0:04:30the person who's been here and done what they've done,
0:04:30 > 0:04:33and we'll see if it continues further up,
0:04:33 > 0:04:37because we know another gunshot's gone into the back of the house.
0:04:37 > 0:04:43The size of the damage to the patio doors is enough to give a good idea of where the gun was fired from.
0:04:43 > 0:04:46So what we've got on the back French doors, here, of the house,
0:04:46 > 0:04:49is a very different pattern, but still a shotgun.
0:04:49 > 0:04:54Whereas on the front door, we had a quite close discharge into the doors,
0:04:54 > 0:04:58here, the shot has gone in from quite a long way away.
0:04:58 > 0:05:03So what's happened is you've gone from a little ball of shot, like my fist, coming towards the door,
0:05:03 > 0:05:07to that ball spreading out and becoming quite a big cone
0:05:07 > 0:05:12and, as you can see from the damage, it's a cone about a metre across,
0:05:12 > 0:05:17so where we're standing now is pretty much where the shot's gone in from.
0:05:18 > 0:05:22Yeah, you've got someone coming down here, officer.
0:05:22 > 0:05:25I have been at scenes where we've had three lines,
0:05:25 > 0:05:28three cordoned lines, all with that tape up,
0:05:28 > 0:05:32and still people have gone through and got in to the inner cordon
0:05:32 > 0:05:34because they're just...
0:05:36 > 0:05:38..people.
0:05:41 > 0:05:46The nature of the shooting suggests it was designed to send the occupants of the house a warning.
0:05:46 > 0:05:51We're aware that it's feuds that generally spark these sort of incidents,
0:05:51 > 0:05:53so it's about either recovering money,
0:05:53 > 0:05:58or making someone do something that the other side want them to do.
0:05:58 > 0:06:01If you wanted to kill someone with a shotgun, it would be very easy to do so.
0:06:01 > 0:06:04What they're doing here is actually damaging the property
0:06:04 > 0:06:06as a scare tactic.
0:06:09 > 0:06:13The team move inside the house to look for any physical evidence related to the attack.
0:06:13 > 0:06:17What they want is the actual gunshot that was fired.
0:06:17 > 0:06:21What we've got here are some of the pellets
0:06:21 > 0:06:24that have been discharged by the shotgun.
0:06:24 > 0:06:26We'll take a representative sample of pellets,
0:06:26 > 0:06:33just so the scientists can give us some information about the type of cartridge that's been used.
0:06:33 > 0:06:38We're looking for a piece that comes out from the shotgun cartridge called a wadding.
0:06:38 > 0:06:39It should be in there somewhere.
0:06:39 > 0:06:45We need to try and find that, because that could be something we could link to the gun, potentially.
0:06:45 > 0:06:47The wadding is a light packing inside the gun cartridge
0:06:47 > 0:06:50that separates the shot from the gun powder.
0:06:50 > 0:06:54When a gun is fired, the wadding follows the shot out of the barrel.
0:06:55 > 0:07:00If found, it can often be matched to the weapon it was fired from.
0:07:00 > 0:07:03We've just found the wadding.
0:07:03 > 0:07:05It's come through the door,
0:07:05 > 0:07:08so we have got that, it could tell us the type of ammunition that's been used,
0:07:08 > 0:07:14if it's been fired from a modified gun, so one that's had the barrel shortened by sawing it off,
0:07:14 > 0:07:17a sawn-off shotgun.
0:07:17 > 0:07:21The little burrs that are created in sawing off the barrel
0:07:21 > 0:07:23will leave marks on the wadding as it comes out of the end,
0:07:23 > 0:07:27and those marks are unique to that barrel, to that gun,
0:07:27 > 0:07:31so we're hopeful that maybe it is a sawn-off shotgun that's been used
0:07:31 > 0:07:34and we'll be able to link that wadding to that gun.
0:07:36 > 0:07:40CID now have a race against the clock to track the culprits down
0:07:40 > 0:07:42and stop them disposing of the weapon.
0:07:42 > 0:07:45Back over at Luton police station,
0:07:45 > 0:07:50every available officer is assisting in the hunt for the gunman.
0:07:51 > 0:07:53Because a firearms incident in the town
0:07:53 > 0:07:58has got potential to be really worrying for the vast majority of people,
0:07:58 > 0:08:01then we need to put the right level of resourcing into it.
0:08:01 > 0:08:05The suspects have been classified as armed and dangerous,
0:08:05 > 0:08:09so a firearms team have been placed on standby to make any arrests.
0:08:10 > 0:08:13It's not long before the police get a tip-off.
0:08:13 > 0:08:18We've had some information that has directly implicated someone.
0:08:18 > 0:08:21If this person can be found by the police,
0:08:21 > 0:08:25Mark's forensic evidence from the scene will be crucial to the investigation.
0:08:26 > 0:08:30It's always very important to me to get the person that did it.
0:08:30 > 0:08:36Because ultimately that's what I'm paid for, but also that's the real kudos that you get
0:08:36 > 0:08:38out of doing any of these jobs.
0:08:38 > 0:08:40Otherwise, why do them?
0:08:42 > 0:08:46The 62 officers who work at the Beds & Herts unit are on call 24/7.
0:08:48 > 0:08:52And there's no let-up today as a call comes in about a vicious attack.
0:08:52 > 0:08:57There's a man in the underpass at Crawley Green Road who's being attacked.
0:08:57 > 0:09:00The police get down there, and there is a man
0:09:00 > 0:09:02and he's very badly injured.
0:09:04 > 0:09:10He's scooted off to the hospital at Luton, and is being cared for.
0:09:10 > 0:09:12He's got serious head injuries.
0:09:12 > 0:09:17He appears to have been burnt with some sort of liquid.
0:09:19 > 0:09:23He's also, as we investigate further, got a stab wound.
0:09:24 > 0:09:27And various other injuries about his person.
0:09:29 > 0:09:32Assisted by fellow officer Caroline Morgans,
0:09:32 > 0:09:35Mark heads straight to the crime scene.
0:09:35 > 0:09:39A bedsit, close to where the victim was found,
0:09:39 > 0:09:41is reported to be covered with blood.
0:09:42 > 0:09:45The essence of our job is looking at that crime scene
0:09:45 > 0:09:50and saying, what has gone on here, can we show through the blood that's at the scene
0:09:50 > 0:09:53who's been attacked and who's been responsible for it?
0:09:53 > 0:09:56The reason that forensic science is so powerful
0:09:56 > 0:10:01is that it's almost impossible to argue with what we've got.
0:10:06 > 0:10:09There's a trail of blood from the pavement
0:10:09 > 0:10:13where the victim was found leading into the building.
0:10:15 > 0:10:18There's a spot of blood on the doorstep here.
0:10:18 > 0:10:21The first thing a Scenes of Crime Officer, a SOCO,
0:10:21 > 0:10:23does at a crime scene is to visually map out the area.
0:10:23 > 0:10:26First things first. Let's see what we've got.
0:10:26 > 0:10:28Then we'll start to put ourselves
0:10:28 > 0:10:32in the mindset of the persons that have been in here and what's gone on.
0:10:32 > 0:10:35You've got to start by finding all the things to be found.
0:10:35 > 0:10:38Mark is looking to isolate the areas
0:10:38 > 0:10:41that immediately stand out as hotspots.
0:10:41 > 0:10:44In the corner of the tiny one-room flat,
0:10:44 > 0:10:47there's an armchair covered in blood.
0:10:48 > 0:10:51A small table is littered with potential evidence.
0:10:51 > 0:10:56And on the floor, a broken kitchen chair, also covered in blood.
0:10:56 > 0:11:03Of the three main hotspots, Mark starts with the kitchen sink,
0:11:03 > 0:11:06which is crammed with seemingly innocent household items.
0:11:06 > 0:11:09It's possible they may have been used as weapons.
0:11:09 > 0:11:14We know our victim has a nasty injury on the top of his head, and there's another one slightly further back.
0:11:14 > 0:11:18And they're circular, or at least part of a circle.
0:11:18 > 0:11:19And if you look here,
0:11:19 > 0:11:23at the bottom of this oven cleaner, you can see it's covered in blood.
0:11:23 > 0:11:26And also, you can see, it's slightly deformed.
0:11:26 > 0:11:31These aerosol cans are meant to take a lot of internal pressure,
0:11:31 > 0:11:33so they don't buckle easily.
0:11:33 > 0:11:35And to make it buckle like that,
0:11:35 > 0:11:38that's taken quite some physical force to do that.
0:11:38 > 0:11:42One of our initial queries was, where did he get injured?
0:11:42 > 0:11:45Well, it's looking increasingly like he got injured in here.
0:11:45 > 0:11:50One of his other injuries is a very sharply angled triangle,
0:11:50 > 0:11:53a mark on his chest.
0:11:53 > 0:11:57Well, the iron's missing its base plate.
0:11:57 > 0:12:00If we can find that, that just further adds
0:12:00 > 0:12:02to what we're already seeing,
0:12:02 > 0:12:07evidence that it happened here.
0:12:07 > 0:12:11And there looks like spattered blood. Can you see right up inside there?
0:12:11 > 0:12:14So it looks like whatever's gone on
0:12:14 > 0:12:17has continued to go on after that bit's come off.
0:12:20 > 0:12:24And then, the caustic soda bottle, covered in blood.
0:12:24 > 0:12:28Our victim has got burns, and they don't appear to be burns
0:12:28 > 0:12:32from a flaming source, they appear to be chemical burns.
0:12:32 > 0:12:34And caustic soda is corrosive
0:12:34 > 0:12:38and very, very nasty if you get it on your skin.
0:12:38 > 0:12:41The extreme violence of the crime
0:12:41 > 0:12:45has left an overwhelming amount of potential evidence.
0:12:45 > 0:12:47It may take days to gather it all.
0:12:49 > 0:12:52On the other side of Luton, there's been a dramatic development
0:12:52 > 0:12:55in the hunt for the gunmen involved in the shooting.
0:12:55 > 0:12:59Two men wanted in connection with the attack have been tracked down.
0:12:59 > 0:13:03They have been named as brothers Zahir and Waseem Baig.
0:13:03 > 0:13:07The firearms team is closing in.
0:14:13 > 0:14:16After giving up peacefully, both brothers are arrested
0:14:16 > 0:14:18on suspicion of carrying out the shooting.
0:14:21 > 0:14:22In the bedsit,
0:14:22 > 0:14:26the team have spent several hours sifting through the room.
0:14:32 > 0:14:34More blood on that.
0:14:34 > 0:14:37In fact, they've gone as far as to break it into parts
0:14:37 > 0:14:39to make it sharp to make it more of a weapon.
0:14:39 > 0:14:41It's significant that we're getting no comment
0:14:41 > 0:14:44from the people that have been detained.
0:14:44 > 0:14:47The questions they can put in further interviews are around
0:14:47 > 0:14:51"Why is the broom handle broken in pieces, with blood all over it?
0:14:51 > 0:14:54"Why is the iron broken in pieces, with blood all over it?
0:14:54 > 0:14:56Whilst the people in custody don't have to answer,
0:14:56 > 0:14:59they don't have to incriminate themselves,
0:14:59 > 0:15:02if they chose not to comment at that stage,
0:15:02 > 0:15:04well, what does that say to a jury?
0:15:05 > 0:15:09There's a silver, curved bar over in the far corner
0:15:09 > 0:15:11in the area of all that blood over there.
0:15:11 > 0:15:18And it's apparent that it's the missing leg from this chair.
0:15:19 > 0:15:22That's got some really interesting blood patterns on it.
0:15:22 > 0:15:24This chair, we're going to take away
0:15:24 > 0:15:26to have a look at in the laboratory,
0:15:26 > 0:15:29because we could be looking at fingerprints,
0:15:29 > 0:15:33we could be looking at DNA, we could be looking at blood pattern.
0:15:33 > 0:15:36So it looks as if this has been deliberately unscrewed
0:15:36 > 0:15:38and then taken and used as a weapon.
0:15:38 > 0:15:40The SOCO team keep up a constant dialogue
0:15:40 > 0:15:42with the detectives heading up the case,
0:15:42 > 0:15:45as they are not allowed inside until the team
0:15:45 > 0:15:47have gathered all potential evidence.
0:15:47 > 0:15:50When we're doing this, we don't let anyone else in to the crime scene.
0:15:50 > 0:15:52We don't want to contaminate it
0:15:52 > 0:15:54before we've got the forensic science evidence out.
0:15:54 > 0:15:57You've got to be mindful that there could be stuff here
0:15:57 > 0:15:59that could let the detectives
0:15:59 > 0:16:02go and follow a line of enquiry that's new
0:16:02 > 0:16:05and could lead them to something good.
0:16:05 > 0:16:08So whilst we're going around poking, looking for blood
0:16:08 > 0:16:11and things like that, we'd also be looking to see
0:16:11 > 0:16:15if there's something that will give us a name for someone who might have been here,
0:16:15 > 0:16:17or might give a reason why this has happened.
0:16:17 > 0:16:20It looks as though any household appliance
0:16:20 > 0:16:23that came to hand may have been used as a weapon.
0:16:25 > 0:16:28Now I've taken it out of the wall, I can see that there's blood
0:16:28 > 0:16:32on one of the pins. So this has clearly been plugged into that wall
0:16:32 > 0:16:34after our assault started
0:16:34 > 0:16:39or, you know, after our victim started bleeding.
0:16:39 > 0:16:42The fact that it's now bare ends of the wire
0:16:42 > 0:16:44just makes it even more sinister.
0:16:46 > 0:16:48Mark is still looking for the knife
0:16:48 > 0:16:51that may have been used to wound the victim.
0:16:54 > 0:16:58Well, it hasn't got obvious blood on it, has it?
0:16:58 > 0:17:02It's not the one that's been used to stab our man in the chest.
0:17:02 > 0:17:05Mark and Caroline have already identified
0:17:05 > 0:17:09and catalogued 17 pieces of evidence.
0:17:09 > 0:17:14But the sheer volume of material means the team will return tomorrow to continue their investigation.
0:17:17 > 0:17:18We've had a good day.
0:17:18 > 0:17:22Got a load of exhibits, a lot of very good exhibits.
0:17:22 > 0:17:26Time now, really, to take it back to the police station.
0:17:26 > 0:17:28Some of it, we'll take in the laboratory
0:17:28 > 0:17:31and start work on it, and the rest of it, we'll use
0:17:31 > 0:17:34with the detectives to see what the detainees have got to say about it.
0:17:38 > 0:17:42A policeman will stand guard at the property overnight.
0:17:44 > 0:17:48At the Baig brothers' house, a major search is underway.
0:17:48 > 0:17:52CID have made a discovery in the boot of a car on the driveway,
0:17:52 > 0:17:56and SOCO Ruth Precious has been called in to investigate.
0:17:56 > 0:17:59We think we may have some firearms in the boot of the vehicle,
0:17:59 > 0:18:03but until they've been photographed, they obviously can't be recovered.
0:18:03 > 0:18:07I can't recover them if they're loaded.
0:18:07 > 0:18:11So we have to give the firearm officers the equipment
0:18:11 > 0:18:13to actually do the recovery.
0:18:13 > 0:18:16Lying in the boot is a Beretta 12 gauge shotgun,
0:18:16 > 0:18:21- designed for shooting pheasants. - Excellent news.
0:18:21 > 0:18:25This one has been modified for use by the underworld,
0:18:25 > 0:18:28with both its barrels crudely sawn off.
0:18:31 > 0:18:36Alongside the gun is a plastic carrier bag, filled with cartridges.
0:18:42 > 0:18:44When it goes off to the laboratory,
0:18:44 > 0:18:46they'll be able to say when it was fired
0:18:46 > 0:18:50and whether that matches the other incident that we've got connected.
0:18:50 > 0:18:52I believe this morning,
0:18:52 > 0:18:57the actual damage it did to the front door was quite,
0:18:57 > 0:19:00quite bad, so it could have been a person
0:19:00 > 0:19:02and it'd have been a body we were going to,
0:19:02 > 0:19:06not just a recovery of a firearm. So it's nice to get one off the streets.
0:19:06 > 0:19:10Whilst the gun is sent to the lab, the car it was found in
0:19:10 > 0:19:13is sent to the police station for fingerprinting.
0:19:14 > 0:19:18What I'm going to do is a fingerprint examination
0:19:18 > 0:19:23of the vehicle, starting off with the boot area.
0:19:23 > 0:19:26Now that all the DNA sampling has been done,
0:19:26 > 0:19:28I can do the fingerprinting.
0:19:28 > 0:19:32We always do the DNA examination first,
0:19:32 > 0:19:37so we don't contaminate the DNA with our fingerprint powder.
0:19:38 > 0:19:42As you can see, the vehicle's quite dirty, so that kind of limits
0:19:42 > 0:19:48our chances of finding fingerprints, but it's always still worth a try.
0:19:48 > 0:19:51Fingerprint powder is made of aluminium dust.
0:19:51 > 0:19:54Effective on a variety of surfaces, the fine metal particles
0:19:54 > 0:19:58attach themselves to the ridges of even the faintest fingerprint.
0:19:58 > 0:20:01There's some ridge detail in that print there,
0:20:03 > 0:20:06so what I'm going to do is lift that.
0:20:06 > 0:20:10I can see some characteristics in that mark there,
0:20:10 > 0:20:12so it's still worth me lifting it
0:20:12 > 0:20:16and I'll let the fingerprint experts make the decision.
0:20:16 > 0:20:21It's always quite rewarding when you find a little bit of evidence,
0:20:21 > 0:20:24knowing that it might identify somebody.
0:20:24 > 0:20:28It's like playing a game of Cluedo, but it's actually the real thing.
0:20:30 > 0:20:32The suspects Zahir and Waseem Baig
0:20:32 > 0:20:34are offering no information to the police.
0:20:34 > 0:20:36This means that Ruth needs to try
0:20:36 > 0:20:40and prove the Baig brothers handled the weapon.
0:20:45 > 0:20:48Ruth starts swabbing down the gun
0:20:48 > 0:20:52and its case, looking for any traces of DNA.
0:20:52 > 0:20:55Whoever pulled the trigger will leave their DNA on here,
0:20:55 > 0:20:57but also fingerprints.
0:20:57 > 0:21:00Maybe more than one person may have handled it.
0:21:00 > 0:21:03Vijay has finished dusting the car, and has now moved on
0:21:03 > 0:21:05to testing the cartridges
0:21:05 > 0:21:08and the carrier bags they were found in.
0:21:08 > 0:21:11The whole purpose of fingerprinting these carrier bags
0:21:11 > 0:21:14and DNA swabbing those cartridges is to try and determine
0:21:14 > 0:21:18who's had contact with the carrier bags and the ammunition.
0:21:18 > 0:21:21It's always quite reassuring when you get things like this
0:21:21 > 0:21:23being submitted for examination.
0:21:23 > 0:21:26You know you've actually taken these cartridges off the street,
0:21:26 > 0:21:28and that firearm as well.
0:21:28 > 0:21:30Potentially, they could have been used for anything.
0:21:34 > 0:21:36The SOCO team have carried out as much work
0:21:36 > 0:21:40as they can on the retrieved items, with only limited results.
0:21:40 > 0:21:42For more definite answers,
0:21:42 > 0:21:45items are sent to the high-tech scientific services lab
0:21:45 > 0:21:49at Police HQ in Welwyn Garden City.
0:21:51 > 0:21:54Over 6,000 items of evidence are examined here
0:21:54 > 0:21:59every year, making it one of the busiest in the world.
0:22:00 > 0:22:02Technician Jamie Haworth sets to work
0:22:02 > 0:22:05by putting the gun in a fuming chamber.
0:22:09 > 0:22:13We place a small amount of superglue in this foil tray.
0:22:13 > 0:22:18The heating plate will warm up and vaporise the superglue.
0:22:18 > 0:22:20The fuming process relies
0:22:20 > 0:22:22on the vapours released from heating the glue
0:22:22 > 0:22:24spreading around the chamber.
0:22:24 > 0:22:28The sticky fumes then attach themselves to any sweat or grease
0:22:28 > 0:22:31left behind in a fingerprint.
0:22:35 > 0:22:40You're always fully aware in the lab what part we play
0:22:40 > 0:22:42within an investigation,
0:22:42 > 0:22:45and how important our jobs are every single day.
0:22:54 > 0:22:57There's some ridges here,
0:22:57 > 0:23:00so we'll have to have a closer look.
0:23:00 > 0:23:04Ridges are the contours that create a unique fingerprint.
0:23:04 > 0:23:10Any mark Jamie finds needs to have sufficient detail within the ridges
0:23:10 > 0:23:14for them to be of any use in making a positive ID.
0:23:14 > 0:23:16It could be, obviously,
0:23:16 > 0:23:18that somebody's touched it,
0:23:18 > 0:23:21but they've probably touched it so many times
0:23:21 > 0:23:24that any kind of ridge detail has just been swamped.
0:23:24 > 0:23:28OK, so the gun's negative. There's nothing on that.
0:23:28 > 0:23:32So the best chance of linking the Baigs to the shooting
0:23:32 > 0:23:33lies with the gun case,
0:23:33 > 0:23:36or the carrier bags the ammunition was stowed in.
0:23:38 > 0:23:42Jamie has subjected both to the superglue chamber for treatment.
0:23:42 > 0:23:44Seeing some marks that could be prints,
0:23:44 > 0:23:48Jamie uses a high intensity magnetic laser light known as a quasar.
0:23:48 > 0:23:51The light creates a fluorescent effect
0:23:51 > 0:23:55under which even the faintest trace of a fingerprint will glow.
0:23:55 > 0:23:59There's kind of a series of five or six fingerprints.
0:23:59 > 0:24:03You can see that there's some ridge detail,
0:24:03 > 0:24:09with some characteristics and beginnings of a pattern.
0:24:09 > 0:24:12The vital find is photographed,
0:24:12 > 0:24:15so that it can be sent to an independent examiner.
0:24:15 > 0:24:19Richard Luckcraft is one of the UK's leading dactyloscopists,
0:24:19 > 0:24:22or fingerprint experts. His job
0:24:22 > 0:24:23is to test the lab prints
0:24:23 > 0:24:27against those provided by the Baig brothers to see if there's a match.
0:24:27 > 0:24:30It's an old-fashioned machine, but very effective
0:24:30 > 0:24:32in that it does the job.
0:24:32 > 0:24:36The technology he is using may appear antiquated,
0:24:36 > 0:24:38but the results mean that it remains
0:24:38 > 0:24:42at the forefront of any forensic investigation.
0:24:43 > 0:24:46No two fingerprints are the same.
0:24:46 > 0:24:50Computer evidence for fingerprints is inadmissible in court.
0:24:50 > 0:24:52A positive fingerprint identification
0:24:52 > 0:24:54still has to be made by eye.
0:24:54 > 0:24:58We're just looking for the quality of the characteristics.
0:24:58 > 0:25:01As soon as we're satisfied
0:25:01 > 0:25:05that the ridge characteristics agree with, are in the same position,
0:25:05 > 0:25:08the same relationship to each other,
0:25:08 > 0:25:11in both the mark and the print, then we're happy,
0:25:11 > 0:25:13we're satisfied it's an identification.
0:25:17 > 0:25:22No-one else in the world has this type of formation of characteristics.
0:25:25 > 0:25:28Yep. I'm satisfied that that's an identification.
0:25:28 > 0:25:33Richard's work will be checked by two further independent experts,
0:25:33 > 0:25:36as a confirmed fingerprint on an illegal weapon
0:25:36 > 0:25:39is enough to send someone to jail.
0:25:39 > 0:25:43He passes his findings to the detectives leading the investigation
0:25:43 > 0:25:47who are now confident Zahir Baig has handled the gun.
0:25:47 > 0:25:50Clearly now what we have, evidentially, is that
0:25:50 > 0:25:56Zahir Baig is in contact with the bag that held the ammunition
0:25:56 > 0:26:00and the gun in the case, or the case that held the gun.
0:26:00 > 0:26:05What we need to prove now is that gun is responsible for discharging the round
0:26:05 > 0:26:10cos then we can prove not only possession of a prohibited weapon,
0:26:10 > 0:26:13we can also prove their involvement in discharging a firearm
0:26:13 > 0:26:16with, you know, intent to endanger life,
0:26:16 > 0:26:20so it is a very important step still in the inquiry.
0:26:20 > 0:26:22GUNSHOT
0:26:23 > 0:26:27Dr Philip Alexander is a forensic firearms expert.
0:26:27 > 0:26:32With over 25 years' experience, he's worked on over 5,000 cases.
0:26:33 > 0:26:38Detective work and science in general are very much the same.
0:26:38 > 0:26:41He links ammunition and casings from a crime scene
0:26:41 > 0:26:43to the guns that fired them.
0:26:43 > 0:26:47No two weapons will ever be the same.
0:26:47 > 0:26:51The test on the range is designed to prove that the wadding
0:26:51 > 0:26:55found on the crime scene has the same markings as the wadding
0:26:55 > 0:26:58left behind from any cartridge fired in the lab.
0:26:58 > 0:27:02At this point you might want to turn the volume down on your instrument
0:27:02 > 0:27:04to prevent any damage.
0:27:04 > 0:27:08These are on laboratory ammunition fired in the case gun.
0:27:12 > 0:27:15Stand back. Firing.
0:27:15 > 0:27:17GUNSHOT
0:27:17 > 0:27:21And there's the fired plastic wad that was part of the cartridge.
0:27:21 > 0:27:24The theory is that the sawn-off barrel of the weapon
0:27:24 > 0:27:27places tiny unique tear marks in the fabric of the wadding
0:27:27 > 0:27:29as it passes out of the barrel
0:27:29 > 0:27:32and could be used to prove there is a direct match.
0:27:34 > 0:27:39Recovered from the crime scene itself were these four items.
0:27:39 > 0:27:41Two 12-gauge plastic cup wads
0:27:41 > 0:27:45and two samples from separate locations
0:27:45 > 0:27:48of impact-damaged lead shot pellets.
0:27:48 > 0:27:54You can see that we have a particular type of 12-gauge wadding,
0:27:54 > 0:27:56and I've examined these cartridges
0:27:56 > 0:28:00and I have noted that this one has that type of wadding loaded within it
0:28:00 > 0:28:04and it's a very unusual cartridge because it's a tracer cartridge.
0:28:04 > 0:28:10It contains a single tracer bulb.
0:28:10 > 0:28:14Tracer cartridges are often used as a training aid for clay-pigeon shooting.
0:28:14 > 0:28:18The tracer bulb creates a visual trail when the gun is fired,
0:28:18 > 0:28:21enabling the marksman to perfect his shot.
0:28:22 > 0:28:26Because I had never seen this before in a criminal cartridge case,
0:28:26 > 0:28:29the fact the materials recovered from the crime scene
0:28:29 > 0:28:33are the same as the materials recovered in this cartridge,
0:28:33 > 0:28:35that is evidentially significant.
0:28:35 > 0:28:39The evidence against the Baig brothers appears to be overwhelming.
0:28:39 > 0:28:43Both are charged with the attack and kept in custody.
0:28:43 > 0:28:45In the bedsit case,
0:28:45 > 0:28:49the forensic team are spending their second day in the flat.
0:28:50 > 0:28:53Three suspects are now in custody.
0:28:53 > 0:28:56Tenant Jennifer Collins, her friend Jackie Kerr
0:28:56 > 0:28:58and her neighbour Barry Medlock.
0:28:58 > 0:29:00The trio claim they had nothing to do with the attack
0:29:00 > 0:29:03and that the victim came to the flat seeking first aid.
0:29:07 > 0:29:10What we're hoping to achieve today is that
0:29:10 > 0:29:13number one, we'll have been able to prove
0:29:13 > 0:29:17whether the victim was assaulted in the flat at Crawley Green Road
0:29:17 > 0:29:21or whether that's somewhere he's gone to after he's been attacked.
0:29:21 > 0:29:25They need to work fast because the bedsit presents a health hazard.
0:29:25 > 0:29:29There's a blue bottle that's come in
0:29:29 > 0:29:33and they're attracted by the smell of the decaying blood.
0:29:34 > 0:29:39And they'll actually start to lay their eggs very shortly, I would think.
0:29:39 > 0:29:44Analysis of blood markings is one of the SOCO's key skills.
0:29:44 > 0:29:47When blood is spilled, it can leave crucial evidence behind.
0:29:47 > 0:29:52Not only relating to who the victim was, but how the attack evolved.
0:29:52 > 0:29:58Someone with blood on their hands has put their hand against this door
0:29:58 > 0:30:02and their hands, because it's got so much blood on it, has slipped.
0:30:02 > 0:30:05That's why you've got these marks here.
0:30:05 > 0:30:08So either it's our victim,
0:30:08 > 0:30:11he's got blood on his hands, he's trying to escape,
0:30:11 > 0:30:15he's stumbled, or perhaps it's an offender who's done the same thing,
0:30:15 > 0:30:19who's slipped and put their hand against the door frame.
0:30:23 > 0:30:25Swabs are taken of the door markings
0:30:25 > 0:30:28for any DNA that may have been left behind.
0:30:29 > 0:30:32The analysis moves onto other patches and specks of blood,
0:30:32 > 0:30:35which are all around the room.
0:30:35 > 0:30:40Mark is looking for what is known in the trade as blood-spatter patterns.
0:30:41 > 0:30:45It would appear that that is a spatter pattern.
0:30:45 > 0:30:47That's someone who's been bleeding already
0:30:47 > 0:30:50and has then been repeatedly hit with something,
0:30:50 > 0:30:55causing the blood to just flick off in spatters, just like that.
0:30:56 > 0:31:01And hit on the wall in these characteristic sort of arcs.
0:31:02 > 0:31:03On the previous visit,
0:31:03 > 0:31:07Mark identified a chair with a leg broken off.
0:31:11 > 0:31:14His theory is that the leg may have been used as a club
0:31:14 > 0:31:17to beat the victim about the body and the head.
0:31:20 > 0:31:22Looking at this sofa more and more,
0:31:22 > 0:31:26that really looks to me like someone's head.
0:31:26 > 0:31:30Given his injuries - he's got one stab wound here,
0:31:30 > 0:31:31side of his left chest.
0:31:31 > 0:31:35Most of the rest of it is his head,
0:31:35 > 0:31:39and head wounds bleed really heavily, really quickly,
0:31:40 > 0:31:42and so my judgement at the moment
0:31:42 > 0:31:48is that that is where his head's been for quite a sustained attack.
0:31:48 > 0:31:52The direction of the blood flying upwards and sideways across the wall
0:31:52 > 0:31:55directly correlates to the way blood would spray
0:31:55 > 0:31:58had repeated blows been rained upon the victim's head.
0:31:58 > 0:32:01The DNA is certainly going to give them a lot of questions
0:32:01 > 0:32:04that they've got to answer, as to why there's so much
0:32:04 > 0:32:07of the victim's blood deposited - if it is the victim's blood -
0:32:07 > 0:32:09on the wall in that pattern.
0:32:09 > 0:32:12At the end of the day, our victim got a good beating in here
0:32:12 > 0:32:14and was lucky that he didn't die,
0:32:14 > 0:32:17so I'm satisfied that we've got a lot of evidence
0:32:17 > 0:32:20that can help find out who did it.
0:32:21 > 0:32:25Mark's hoping that now the delicate forensic evidence has been gathered
0:32:25 > 0:32:29he can make a final search for the missing knife.
0:32:29 > 0:32:31We're carrying on the bits we haven't already searched
0:32:31 > 0:32:35because they were inaccessible or we didn't want to move other stuff.
0:32:35 > 0:32:38Just seeing what we've got, really.
0:32:43 > 0:32:44Well, that might be it.
0:32:44 > 0:32:48It's a Stanley knife, down the side of the bed.
0:32:50 > 0:32:52Shall we get a blood test?
0:32:52 > 0:32:55It's not got a very long blade. It's a very sharp blade
0:32:55 > 0:33:00and without the medical notes to say exactly how deep his stab wound is...
0:33:00 > 0:33:03That would fit with some of the other wounds he's got,
0:33:03 > 0:33:05particularly across his fingers.
0:33:05 > 0:33:08We're trying to see whether the stains we can see on the blade,
0:33:08 > 0:33:11that might be blood, are blood.
0:33:13 > 0:33:18And that's indicating that there could well be blood on it.
0:33:18 > 0:33:22So we'll package that up and send it off with the other exhibits
0:33:22 > 0:33:25to the scientists, to see if we're right.
0:33:25 > 0:33:30It's always good to find things that are useful to the inquiry.
0:33:30 > 0:33:33Mark has spent two days painstakingly combing the bedsit
0:33:33 > 0:33:35for clues and evidence.
0:33:35 > 0:33:38He now has a comprehensive picture of what happened.
0:33:38 > 0:33:41He thinks that the victim was attacked
0:33:41 > 0:33:43while sat in the corner armchair.
0:33:43 > 0:33:45There is evidence he was kicked and punched.
0:33:45 > 0:33:48The attackers used a variety of clubs in the assault,
0:33:48 > 0:33:53which left a series of distinctive blood patterns on the wall.
0:33:53 > 0:33:56On top of this, the already bleeding victim was attacked
0:33:56 > 0:33:59with a number of items Mark found by the sink.
0:34:02 > 0:34:05He was beaten with the iron so hard that it broke,
0:34:05 > 0:34:08battered with an aerosol can,
0:34:08 > 0:34:11and whipped with a piece of flex.
0:34:11 > 0:34:15At some point in the night-long ordeal the beatings turn to torture,
0:34:15 > 0:34:17as the victim is covered with caustic soda
0:34:17 > 0:34:20and then soaked in water from the kettle,
0:34:20 > 0:34:22giving him severe chemical burns.
0:34:22 > 0:34:24He was also slashed and stabbed
0:34:24 > 0:34:28before being manhandled through the door and left in the road.
0:34:28 > 0:34:32His life was saved when a passer-by called the emergency services.
0:34:32 > 0:34:37It makes the hard work of the five or six hours we spend in here,
0:34:37 > 0:34:41dressed like this, worthwhile.
0:34:44 > 0:34:48It's now time for the detectives to make the best use of the evidence
0:34:48 > 0:34:50and bring the case to court.
0:34:56 > 0:34:59In the case of the intimidation shooting,
0:34:59 > 0:35:02fingers were pointed immediately to the Baig brothers
0:35:02 > 0:35:04but it was up to Mark and the SOCO team
0:35:04 > 0:35:06to prove the brothers carried out the shooting.
0:35:06 > 0:35:10The intended victim no longer lives at the address.
0:35:10 > 0:35:13Although the weapon found in the Baigs' car was clean,
0:35:13 > 0:35:17fingerprints on the gun case were proved be those of Zahir Baig,
0:35:17 > 0:35:19and the unique markings on the cartridge wadding
0:35:19 > 0:35:20found at the scene,
0:35:20 > 0:35:24combined with the unusual tracer ammunition,
0:35:24 > 0:35:28proved it was this same gun that had been used in the shooting.
0:35:28 > 0:35:31A tip-off placed Waseem Baig at the scene
0:35:31 > 0:35:34and faced with all the evidence, he pleaded guilty
0:35:34 > 0:35:36to using the shotgun for intimidation,
0:35:36 > 0:35:38and two other weapons charges.
0:35:38 > 0:35:42He was sent to jail for five and a half years.
0:35:42 > 0:35:46His brother Zahir also pleaded guilty to firearms charges
0:35:46 > 0:35:48and was sentenced to five years.
0:35:48 > 0:35:51Once the full forensic evidence was put to the three suspects
0:35:51 > 0:35:53in the torture house,
0:35:53 > 0:35:58only one, Barry Medlock, denied his part in the assault.
0:35:58 > 0:36:02But he was found guilty of causing grievous bodily harm with intent
0:36:02 > 0:36:05by a jury at Luton Crown Court.
0:36:05 > 0:36:08Tenant Jennifer Collins and her friend Jacky Kerr
0:36:08 > 0:36:11both pleaded guilty to the sustained attack in the bedsit.
0:36:11 > 0:36:15A judge said he was satisfied that Kerr had initiated the beating,
0:36:15 > 0:36:17kicked, punched and clubbed the victim,
0:36:17 > 0:36:21before pouring caustic soda and water over his head and body.
0:36:21 > 0:36:23Kerr was sentenced to eleven and a half years in jail
0:36:23 > 0:36:25for GBH with intent.
0:36:25 > 0:36:29Collins was sentenced to six years and three months.
0:36:29 > 0:36:31Medlock was given eleven years.
0:36:31 > 0:36:34Though severely traumatised by the attack,
0:36:34 > 0:36:40their victim recovered sufficiently from his injuries to give evidence.
0:36:40 > 0:36:43In the past 12 months, the Beds and Herts SOCO team
0:36:43 > 0:36:46have helped to crack more than 8,000 cases -
0:36:46 > 0:36:50almost 20% of all crimes solved in the two counties.
0:36:50 > 0:36:53It's always satisfying, as a scenes of crime officer,
0:36:53 > 0:36:56to find that the evidence you picked up at that crime scene
0:36:56 > 0:36:58and spent hours getting back
0:36:58 > 0:37:01has ended up either making someone admit their guilt
0:37:01 > 0:37:03or being found guilty.
0:37:03 > 0:37:06It's bringing the scene to life for the jury the court,
0:37:06 > 0:37:09so that they can understand, in simple terms,
0:37:09 > 0:37:13exactly what's gone on and what we, the police,
0:37:13 > 0:37:17say the person in the dock is accused of having done.
0:37:37 > 0:37:40Subtitles by Red Bee Media Ltd
0:37:40 > 0:37:44E-mail subtitling@bbc.co.uk