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  • - During my time as a major crimes forensics detective,

  • I worked about 20,000 crime scenes.

  • - [Narrator] Today, Karen is going to break down

  • fictional crime scene investigations

  • to determine what Hollywood gets right and wrong.

  • [dramatic music]

  • - What I want you to understand

  • is that crime scenes are very difficult.

  • There are infinite number of possibilities.

  • So when we go into one,

  • we have to go in with an open mind, with objective means,

  • and we have to gather all of our evidence appropriately

  • so that everything can go to court.

  • First up, "Dexter."

  • In this scene, Dexter, a blood spatter analyst,

  • investigates a crime scene.

  • - Look at the blood spatter, look at the patterns.

  • It tells a story.

  • You see this big pond of blood right there.

  • That's when the initial stab-

  • - This is pure Hollywood.

  • I don't know what a pond of blood is.

  • A pond is what fish are in.

  • A pond is not what blood is.

  • We don't use a term like that.

  • I don't know what all those red strings are either.

  • When we reconstruct what's called an impact pattern,

  • we can take up to six to 10 different, small blood droplets

  • and draw them into three dimensional space.

  • And that's apparently what they were trying to do

  • with these red strings here,

  • but not only is that ridiculous,

  • it doesn't tell me anything

  • about the crime scene whatsoever.

  • - The male victim was standing right here

  • and the killer plunged his knife into the shoulder,

  • severing the carotid artery and [lips sputter].

  • Notice the long thick heavy drips.

  • - That stain on the wall is not like anything we would find

  • at a crime scene.

  • That looks like the prom scene from the movie "Carrie."

  • There's nothing that those strings are attached to,

  • on that wall, that is meaningful at all.

  • I also don't know how you would reconstruct a crime scene

  • using a non-pattern like that

  • and then deduce that the person

  • came across with a knife this way and that way.

  • Crime scene reconstruction is very detailed.

  • It's very objective.

  • So it's not just walking into a crime scene

  • and then just positing what you think happened,

  • based on the patterns at the scene.

  • You have to do a lot of legwork.

  • - Now over here, you have nice clean sprays of blood

  • and that can only happen

  • when you're holding something light and moving quick.

  • Nice sharp slices through the body, no splashes, no drips,

  • clean and easy.

  • - Clean and easy.

  • Hm, if I were to classify what Hollywood

  • has attempted to recreate on that wall,

  • it would be termed something along the lines of cast off.

  • And cast off happens when blood adheres to an object,

  • and that object is swung through the air,

  • and the adhesive properties of blood

  • are overcome by that force,

  • and they land in a linear arc on the available surfaces.

  • And they can leave a line.

  • And depending on weapon used, the line can be very thin,

  • such as with the tip of a knife,

  • or they can be thicker, such as with a baseball bat,

  • or a tire iron.

  • But again, these are things that take the scientific method,

  • they take objective means to measure and to recreate.

  • So this is just nonsense.

  • - So we're looking for a sushi chef.

  • - Yeah, sushi chef is possible.

  • Wouldn't be my first choice, but hey, you never know.

  • - Now what?

  • - Now I eat.

  • - And last but not least, in this clip,

  • nobody's wearing a Tyvek suit.

  • Nobody's wearing shoe booties.

  • Nobody is wearing gloves.

  • He snaps one photograph and splits for dinner.

  • Nothing about this scene has anything to do with reality.

  • Overall, I think this is a Hollywood hot mess.

  • It is a non-forensic nightmare.

  • And I may have a nightmare tonight,

  • now that I've watched it.

  • Next up "Fargo" season two.

  • In this scene, the local detectives

  • investigate a crime scene at a local diner.

  • - Put my coat on her.

  • Seemed only right.

  • - I put my coat on her.

  • Seemed only, right.

  • No, no, no, no.

  • That is only wrong.

  • We never introduce evidence to a body

  • and she's not gonna get cold, I promise.

  • So we've got some pretty major bloodstains

  • at the entrance there.

  • That means we need to find an alternate entry point.

  • We don't wanna walk over those bloodstains

  • because we could alter them.

  • We could introduce our own shoe prints,

  • our own DNA, other things into that crime scene.

  • So as soon as that door was opened

  • and the blood was present there on the floor,

  • trying to find an alternate route

  • would have been the appropriate thing to do.

  • - I count three dead.

  • I saw the waitress in the parkin' lot.

  • - She caught one there then staggered out.

  • Gunman followed, made things permanent.

  • - Well, if the gunmen followed,

  • according to this very, very rapid reconstruction

  • and you have snow outside, you should be able to find

  • some shoe prints in that snow,

  • leading to the body where the waitress was.

  • Along with a bullet trajectory through her body,

  • or a penetrating injury into her body.

  • That can place where the shooter was, where she was,

  • and it may be able to give you

  • some identifiable characteristics in those shoe prints.

  • - How's Betsy?

  • - You mean you didn't call her before you came over?

  • - Well, yeah, just being polite.

  • Give you a chance to talk about your feelin's,

  • should you be so disposed.

  • - She's good, yeah.

  • Ordered this kit of recipe cards, saw it on the TV.

  • So now every night we eat delicacies of the world.

  • - As much as I love this banter, because it's just adorable,

  • that doesn't happen at a crime scene.

  • We keep things clinical.

  • We keep things linear.

  • We keep things objective.

  • Swapping recipes is something that we do outside of work,

  • outside of the crime scene.

  • As tempting as it might be, it's inappropriate.

  • - Skid marks.

  • - Yeah, I see 'em.

  • Of course, connectin' those to this deal here,

  • would be what we call jumpin' to a conclusion.

  • - Maybe, maybe not.

  • I don't know.

  • But here's the thing, you can measure those skid marks.

  • You can take samples of the rubber from those skid marks.

  • You can find out a width of the undercarriage

  • of the vehicle that created them.

  • And maybe it'll lead you to a car.

  • - Based on the number of bodies,

  • I think we got one car too many in the parking lot.

  • - Whoa, he just picked up that money,

  • with what appears to be possibly blood on it,

  • with his gloved hand, and it's a leather glove.

  • It's not a new, clean, latex glove.

  • That is a huge no-no.

  • When you take evidence from a crime scene like that,

  • not only are you contaminating it

  • with things that might be on your glove,

  • he's reached into his pocket, he's held his pen,

  • he's taken notes, he may have even pulled it off

  • with his fingers at some point,

  • so he's introducing all of that onto that dollar bill.

  • And if that is blood on it, that is a major clue.

  • So the first thing that we would have to do is document it,

  • photograph it, test that substance on it

  • to see if it's blood,

  • and then package it appropriately for the laboratory.

  • Next up "Iron Man 3."

  • In this scene, Tony Stark uses some high-tech forensics

  • to reconstruct a crime scene.

  • - [Jarvis] I've compiled a Mandarin database for you sir,

  • drawn from Shield, FBI, and CIA intercepts.

  • Initiating virtual crime scene reconstruction.

  • - We do have tools that will reconstruct

  • a crime scene in three dimensions.

  • There are 3D scanners.

  • They not only take a 360 degree view of the crime scene.

  • They can do ceilings and the floors,

  • so that when we upload it into a computer,

  • we can actually tilt the entire scene

  • and take measurements from one area to another

  • that are extremely accurate.

  • So, although this is really futuristic and cool,

  • it is not that far out of the realm of possibility.

  • - [Jarvis] Heat from the blast

  • was in excess of 3,000 degrees Celsius.

  • Any subjects within 12.5 yards were vaporized instantly.

  • - No bomb parts found

  • in a three-mile radius of the Chinese Theater?

  • - [Jarvis] No, sir.

  • - We just heard that this explosive device

  • created 3000 degrees Celsius.

  • Well, that would be equivalent

  • to about 5,400 degrees Fahrenheit.

  • To give you some comparison,

  • the surface of the sun is 5,700 degrees.

  • So that's some serious math.

  • And if you have an incendiary device like that,

  • that goes off at that high of a temperature,

  • I'm pretty sure that vaporized is the correct term,

  • but there would be a very large blast radius,

  • not just at 12 and a half yards away.

  • It would be a lot bigger.

  • - Talk to me Happy.

  • [dramatic music]

  • When is a bomb not a bomb?

  • - When is a bomb not a bomb?

  • Never.

  • You need four things to make a bomb.

  • You need an energy source.

  • You need a method of containment.

  • You need a method of initiation.

  • And you need some material

  • that will create an exothermic or heat reaction.

  • Without one of those things, it won't work.

  • Next up, "CSI Miami."

  • In this clip, a brand new investigator

  • makes a horrible mistake in the lab.

  • - Talk me through what you're doin'.

  • - Okay, this is the jacket worn by our suspect,

  • Hector Rivera, we believe that he stabbed Gabriel Cervantes.

  • So I'm gonna run what's called a luminol test.

  • - Hey what's luminol.

  • - Luminol is a compound that when it interacts

  • with the iron in hemoglobin it will luminesce.

  • - This is true.

  • Luminol is a chemiluminescent compound.

  • And when it comes into contact with the heme in blood,

  • it will create a bluish green glow.

  • - Anyway you can get that to be even brighter.

  • I just want it to really pop on film.

  • - Yes.

  • - Oh yeah, yeah, that's the money shot.

  • - No!

  • No!

  • The more you spray a liquid like that onto a surface,

  • the more you're going to dilute the stain.

  • That can make it extremely difficult

  • for the DNA analyst to extract the white blood cells

  • that are needed for a DNA analysis.

  • So the fact that he's spraying this luminol on the sleeve

  • and over and over and over again, he's diluting that sample.

  • - My results are zero zip.

  • There's no DNA on the jacket.

  • - I don't see how that's possible.

  • The luminol gave us significant blood spatter.

  • It was actually more than significant.

  • - You shoulda seen it glow, it was amazing.

  • - Oh, I bet it was.

  • Problem is the more luminal you spray,

  • the more you dilute the blood.

  • - Exactly.

  • There's another problem here.

  • He said it was a stabbing