We are in person at the 2024 Animal Forensic Conference in Gainesville, Florida! Dr. G will be interviewing several of the speakers to give our audience a bit of the knowledge gained through the presentations. We will be releasing each interview individually to allow our listeners to find topics of interest.

We all know, or at least think we know, the uses of DNA in criminal cases, but with true crime and criminal drama shows, our expectations may not be realistic. Ginger Clark, DNA Analyst at the University of Florida Veterinary Forensic Sciences Laboratory, discusses the uses of DNA in forensics and answers questions about truth or fact based on what we learn from television and movies.

We would also like to invite our listeners involved in animal cruelty investigations to visit and join the International Society for Animal Forensic Sciences https://isafs.org/

Mentioned in this episode:

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The Animal Welfare Junction is part of the Keep It Humane Podcast Network. Visit keepithumane.com/podcastnetwork to find us and our amazing animal welfare podcast partners.

Our next guest is Ginger Clark, Forensic DNA Analyst.

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Welcome to The Junction.

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Ginger Clark: Thank you for having me.

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DrG: So can you start by telling us what

your background is and how it relates

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to the field of veterinary forensics?

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Ginger Clark: I started out in

conservation and population genetics

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of a variety of different animals.

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My area of expertise is

actually venomous snakes.

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Um, I worked with Canebrake

rattlesnakes for 25 years.

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Um, but the population genetics, you

have to figure out using DNA, what

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is a species and then what are the

populations associated with those species.

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And what you end up doing

is building large databases.

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And so, if your species are animals

of interest, such as hunting animals

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or, um, other animals that are of

significant interest to people,

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you have large databases that you

can use for statistical analyses.

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And so that's where I started was

conservation of population genetics.

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And a wildlife officer asked me

at some point, could I distinguish

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yes or no, is it white tailed deer,

if he gives me a piece of meat.

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And that's basically where I started.

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And the challenge of each of those kinds

of tests and designing the assays was

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really challenging and interesting.

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And then as I started getting cases,

the different kinds of evidence that

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came in, the different questions

that were asked, those are all things

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that, Keep my imagination and just

keep me doing this because it's

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interesting to try and figure it out.

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Yes, trying to figure it out.

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DrG: That's amazing.

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So what, what are the uses of DNA?

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Like how can we use DNA in forensics?

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Ginger Clark: In a forensic situation,

often the question is, if you have

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a blood splatter, is that, what

organism did that blood come from?

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Is it human?

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Is it dog?

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Is it cat?

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Is it, you know, some other animal

that is going to be of interest?

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Um, and then once you know what

species it is, um, if it's a dog,

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does it go to any of these other dogs?

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Whether it's a deceased animal,

an animal that's being abused,

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an animal that's been stolen.

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Can we compare those two

and put them together?

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And DNA can do that, and that's What's

the, the value of DNA is its ability to be

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able to put all those pieces together and

be reliable, relatable, consistent, and

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be able to take that into a court of law.

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So DNA has been validated for humans.

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We use exactly the same methods

and protocols in animal forensics

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so that we can take that to court.

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DrG: One of the things that you talked

about was using DNA to identify an animal

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as a victim and as a perpetrator, which

we kind of, kind of make sense, but

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then you also discussed about using it

to find out if an animal is a witness.

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So how can animals be

witnesses of a crime?

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Ginger Clark: What happens there

is, the first case of that was a

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man who murdered his girlfriend and

he owned a large, fluffy, white cat.

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And they found that cat's hairs on the

woman whom he said he did not know.

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And so they were able, and they found

those same cat hairs on the jacket

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that he wore when he killed her.

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And they were able to do DNA to

say that those two hairs came

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from the same individual animal.

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So there the cat, by proxy, was a witness.

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And I've done a couple of cases where

it's essentially the same thing.

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Either the suspect has an animal or the

victim has an animal, and that animal's

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DNA shows up on the other person,

and that ties those two individuals

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together in a fairly compelling way

and often in a specific time and space.

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DrG: We talk a lot about the CSI effect,

and I think that DNA is probably one

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of the fields most affected by it.

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How is the public perception wrong

as far as what they expect out of DNA

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based on these shows that they watch?

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Ginger Clark: They assume that it's,

it always works, which it does not.

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They assume that it's fast, uh,

it takes more than 45 minutes.

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Um, And they assume

that it is always right.

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And that's not necessarily the case.

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And the expectation that DNA is going

to have all of the answers is incorrect.

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On TV you see DNA going into a machine

and minutes later it pops up an

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answer with the person's name, date,

birth date, and all this other stuff.

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And often what we get

is "That's interesting.

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Now let's do whatever we can

to see if we can match it to

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something and put it together".

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DrG: I think another misconception

is just the cost, right?

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Like, people think that DNA should

be done in every single case, but

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that's not really feasible, right?

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Ginger Clark: It is not feasible

and it's not always the answer.

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I prefer to do cases where The

officers have really done their

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homework, because then I know it's

probably going to be successful.

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Um, but it's not inexpensive, and

it's not, you know, one of the

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things that happens in human is the

expectation that there's DNA for

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everything, including a bounced check.

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It doesn't, you It doesn't

apply to all the questions.

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DrG: So what type of, what type of

crimes can DNA be used in, in animals?

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Ginger Clark: When we're looking

at animals, if there's um, an abuse

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situation, um, an animal has been beaten,

if there is blood on, say the wall as well

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as the victim, uh, and the perpetrator.

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So we can match those together so we

can put together the the victim and the

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suspect to be able to say this person

inflicted whatever harm it was on an

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animal based on them both having the DNA.

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So DNA gets shared back and forth.

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But certainly cases where animals

are stolen, um, where horses are

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stolen and slaughtered for food, um,

if we can find meat in the freezer,

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blood on the fellow's clothes.

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So it's, it's applicable

to a lot of situations.

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Um, is it a stolen dog?

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Is it, you know, is that the stolen dog?

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Is that the dog's parents?

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So it's not always an abuse thing.

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You know, there might be a question

of paternity of the animal.

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You know, a stolen dog.

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I will still have the dog's bed.

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That looks like my dog.

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Is it the same one?

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DrG: So speaking of paternity, I

discussed with you a little bit ago,

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an interesting case, and I'm changing

a little bit the facts of the events

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of the case, but basically somebody who

bred a dog that had won all of these

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championships, uh, so like a dog show,

award winning dog, and the dog died.

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So the owner said that he had some

of this dog left over and he cloned

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the dog so that he could then sell

the puppies from this cloned dog for

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a high price because it's a show dog.

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So the puppies supposedly would

be coming from the show dog.

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So can DNA help us

determine if that is fraud?

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Ginger Clark: Yes, it can.

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Um, once you have DNA from the so called

clone dog, you have DNA from the puppies.

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If this dog was used for breeding prior

to its death to his death, then you

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would have other puppies and potentially.

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that deceased dog's parents.

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So with that kind of DNA, you can then

look to see what the, uh, paternity is.

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So yes or no, you know, is this dog,

especially if you have puppies prior,

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you should be able to look at that DNA

and say half the DNA comes from him

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with the prior puppies, half the DNA can

be accounted for by him with the next

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group of puppies.

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So yeah, maybe it is a clone.

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In all likelihood, what you'll

find is the DNA from the prior

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puppies doesn't match and cannot

account for that dog being a parent.

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DrG: You were talking about illegal

like meats, um, and that makes me

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think also about the illegal wildlife

trade , so is DNA useful in that?

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Ginger Clark: Yes, it is.

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There's extensive work that's been done

with rhinos and elephants in particular

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and some of the big cats looking at their

DNA and being able to determine where

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those animals were poached from and in

some cases tie them back to specific

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um, poaching rings and um, it's often

associated with drugs and guns and,

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uh, a lot of other illegal activities.

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But the DNA can often identify the

specific, especially with, um, elephants.

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Uh, we can identify the cartel that

has taken that animal and know

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exactly where it's gone, uh, based

on the DNA and the work that's been

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done by colleagues in that field.

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DrG: Any investigators that are

listening to this that are interested

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in submitting DNA, what samples should

they be looking to collect and how

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should they handle those samples?

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Ginger Clark: The samples are going to

be, uh, you sort of need to think about,

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where are you going to get your DNA from?

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So, plucked hairs, plucked

feathers, pieces of hide.

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Pieces of tissue, uh, blood swabs, so

swabs of blood from surfaces, from

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individual animals, clothing, so there's

a whole variety of samples that can be,

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that have the appropriate DNA on it.

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You have to think about your question and

therefore what samples are likely to have

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the DNA that will answer those questions.

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And then submitting it is, you know, once

we're contacted for something, um, we have

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information on how to package and send

material, you know, dry, wet, um, frozen.

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So it needs to be sent quickly and with

a good chain of custody on it because

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you want to be able to take it to court.

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DrG: What are the biggest errors

or mistakes that investigators

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will do when making a submission?

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Ginger Clark: The biggest mistakes

tend to be, with tissue or other

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samples that are messy and not double

bagging, not freezing and sending it

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overnight, not bagging sandy things well,

putting two pieces of evidence in the

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same bag and they should be separate.

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So it's, it's usually a packaging issue

and then not mailing it appropriately.

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Um, if you have something that's

frozen and being sent, it should

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be sent overnight and not ground.

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DrG: So

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Ginger Clark: a lot of problems, I

would say, with like contamination from

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Often there's contamination within a

case that we receive because it hasn't

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been, the individual items have not

necessarily been packaged appropriately.

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And so they touch and contaminate.

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DrG: We know about using DNA for

like criminal cases, but is there

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a use of DNA in like civil cases?

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Ginger Clark: Yes.

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Yes.

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I often do civil cases and often

they're associated with dog maulings.

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So someone is mauled by a dog.

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Uh, there is, there can be a criminal

component to it, but often it's the

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civil case that comes out of it.

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So your dog killed my dog.

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You're not controlling your

dog is a criminal case.

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Um, my loss of companionship,

that's now a civil case.

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So yes, we do have cases that

are civil as well as criminal.

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DrG: So overall, what's the most

common type of cases that you

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are, uh, asked to, to look into?

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Ginger Clark: I, I always have dogfighting

cases, often have cockfighting, and I

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also do a lot of death investigations.

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Where, or near death investigations

where it's, the victim has been, mauled

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or, you know, injured in some way.

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So those are probably the most

common ones at the moment.

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DrG: Excellent.

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Well, thank you very much for

sharing your knowledge and thank

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you for everything that you do.

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Ginger Clark: Thank you for having me.