STATE V. MOTT: A CASE STUDY

IN FORENSIC SCIENCEGraham Polando

Deputy Prosecuting AttorneyElkhart County, Indiana

Elkhart County YMCA

Kari’s Family’s CarFound at 1527 Morton Ave.; Jan. 30, 1991

Kari is Found: February 5, 1991

Bonneyville Mill County Park Dwight Miller’s In-Court Testimony

Q: And what was it that you saw?

A: The nude body of a female…I immediately jumped out of the truck….and as I went around the front of the truck, I started yelling Kari’s name….just screaming it out, I think, more than anything, to get a response or whatever…

The Autopsy: Dr. Rick Hoover

Forensic Pathologist for South Bend Medical Foundation

B.S., Biochemistry, Manchester College

M.D., Indiana University School of Medicine

1,200 Autopsies in 26 Years of Practice

Dr. Hoover’s Findings

•Prolonged Cold Environment Exposure•Soft tissue damage to lips and cheek•Blunt Trauma Injury to Head•“The most significant injury she had was not really a direct injury, but it’s an anatomic marker…petechial hemorrhages around the periorbital area.”

Petechial Hemorrhages

“Marker” Injury

Eyes and Neck

Suddenly stop But no abrasions

Sexual Assault Examination

Physical examination of each orifice

Swabs are used in each orifice to create slides for staining Extracts both skin and fluids

In-Court Testimony onCause of Death

“It would be my opinion that [Kari] died as a result of asphyxia due to cervical compression and secondarily to vaginal injuries.”

“My opinion is Kari’s death is a homicide.”

Limitations on the Investigation

Primitive Available Testing: Blood Group Testing (Type) Lab Technician: “Spermatozoa were observed on the

vaginal smear slides…” Restriction Fragment Length Polymorphism (RFLP)

Mary Reed, Forensic Biology Supervisor for the Indiana State Police: “I would have consumed or used up the entire standard…

in an attempt to get a profile.” “There would be new extraction processes and also new

technologies on the horizon…”

Police investigation ends later in 1991 with no arrests

DNA Analysis since Kari’s Death

Polymerase Chain Reaction (PCR)

Short Tandem Repeat (STR)

Mitochondrial DNA (mtDNA)

Y-Chromosome Analysis

Polymerase Chain Reaction (PCR)

Replicates DNA from even small amounts of biological material Likewise replicates contaminants

Short Tandem Repeats (STR)

Nuclear DNA Polymorphic Loci Nucleotides repeat Result is number of

repeats Produces two numbers:

one from each chromosome

Warming the Cold Case

Evidence sits in Elkhart Police Department storage locker until 2005

Elkhart County Sheriff Mike Books refers case to Indiana State Police Cold Case Unit

Thomas Littlefield, ISP

Cold Case Specialist Noted Advances in DNA

Analysis Starts with…

Fred Mott

Train tracks encounter 1527 Morton Avenue

connection Female screams from

apartment Carrying object

“wrapped up like a carpet”

Loan application Fled Large amounts of

plastic

Fred Mott, California State Prisoner P19833

California State Prison, Lancaster Serving Life Sentence

for 1998 Rape of UC-Berkeley Student

Unclear: Warrant or Consent?

Federal Express shipped from South Bend airport to Reliagene Technologies (now Orchid Cellmark)

Reliagene (Now Orchid Cellmark)

Why a private laboratory? Competent

FQS-I Accredited Quick Objective Admissible Hearsay

What Reliagene Had

What Reliagene Did

8-Loci Reliagene ProfileMini-STR Results

Locus

07-05734

Generic Sample from

Kari

07-05735.01

Vaginal Epithelial Cells

07-05735.02

Sperm Isolated from Vaginal

Epithelial Cells

03-14372

Blood from Fred Mott in California

D8S1179 13,16 13,16 NR 10,14D21S11 29,30 29,30 30 29,31.2D7S820 10,11 10,11 8,9 8,9CSF1PO 12 12 7,10,12 7,10

D3S1358 15,18 15,18 NR 15,17TH01 6,9.3 6,9.3 NR 7,8

D13S317 8,12 8,12 12 12D16S539 10,13 10,13 [10],11,13 11,13D2S1338 20,23 20,23 [20],23,24,25 24,25D19S433 13,14 13,14 NR 11,16.2

vWA 16,17 16,17 NR 15,17TPOX 9,11 9,11 NR 8,9

D18S51 15,17 15,17 14,15,19 14,19AMEL X X X,[Y] X,Y

D5S818 12,13 12,13 NR 10,13FGA 20,22 20,22 [21],22 21

Ms. Nasir’s Conclusions

Q: “Is the profile on the sperm fraction…the same as that from the blood sample of Fred Mott?”

A: “Yes. The profile obtained from the sperm fraction…are [sic] consistent with Fred Mott’s DNA sample. So therefore, Fred Mott is not excluded as a DNA Donor in the sperm fraction.”

Q: “You use the term, ‘not excluded.’ What does that mean?...”

Role of Probabilities

Different Profiles: Individual could not have contributed

Identical Profiles: Individual could be an “exact match” or simply “cannot be excluded.”

“Exact Match” vs. “Cannot be excluded”: Exact Match must:

Be single source and exceed 1 in 5.9 trillion

Cannot be excluded: will produce probability > 1 in 5.9 trillion

Ms. Nasir’s Probabilities

“For this sample, the probability of someone having any possible combination of this profile is 1 in 862,000 individuals of Caucasian descent,

and 1 in 546,000 individuals of African-American

descent.”

Are these probabilities of innocence?...

The Prosecutor’s Argument

“And then we have the DNA analysis. [Defense counsel] would lead you to believe that because they say it’s not a match, that’s not good enough. But, again, you were here; you observed; the evidence was quite clear. The only time we talk about a match is when it’s 5.9 trillion. That’s impossible…”

The Prosecutor’s Argument

“…There’s [sic] six billion people on earth. That would mean one thousand times more people on earth is when they can say it’s a match. That’s because it’s science, ladies and gentlemen. And science has to have their statistics. But you don’t have to worry about that, because as we’ve explained, this hooks up to the facts. And as you see the DNA profiles, it was Fred Mott.”

Appellate Issue: Prosecutorial Misconduct “Mott claims this is a misstatement of the evidence

because ‘[t]here could be a DNA “match” even if there were far fewer people on the Earth.’”

Indiana Court of AppealsMott v. State

“The evidence established that Mott was not excluded as a contributor and

that the probability of someone having any possible combination of the relevant DNA profile was: 1 in 862,000 individuals of Caucasian descent

and 1 in 546,000 individuals of African-American

descent.”

Indiana Court of AppealsMott v. State

“The prosecutor did not overstate the significance of the DNA evidence, which constituted substantial evidence of Mott’s guilt.”

The Prosecutor’s Fallacy?

Thompson, W. & Schumann, E. (1987). Interpretation of Statistical Evidence in Criminal Trials: The Prosecutor’s Fallacy and the Defense Attorney’s Fallacy. LAW AND HUMAN BEHAVIOR 11(3), Sept. 1987, pp. 167-187.

The Prosecutor’s Fallacy?

Thompson and Schumann: Saw a jury trial in which Defendant (known)

and Perpetrator (unknown) shared a blood type common to 10% of the population

Prosecutor: “90% chance Defendant is perpetrator”

Thompson and Schumann’s Hypothetical

All lawyers own briefcases.

One in ten people in the general population own a briefcase.

Jim owns a briefcase. What is the probability

Jim is a lawyer?

Answer

90%?

What are the relative numbers of lawyers and non-lawyers in the population?

Thompson and Schumann: “To draw conclusions about the probability a criminal suspect is guilty based on evidence of a ‘match,’ we must consider not just the percentage of people who would match but also the a priori likelihood that the defendant in question is guilty” (p. 170).

Bayes’ Theorem

Jury: “25% chance Defendant is guilty”

New evidence: Hair found at crime

scene matches only 1% of population

Defendant member of that 1%

97% guilty, not 99% Prosecutor’s

Argument: “This hooks up to the facts.”

Broun, K., Mosteller, R., and Giannelli, P. (2002) EVIDENCE: CASES AND MATERIALS (6th Ed.) (citing Finkelstein & Fairley, 1970).

Guilty

“Rapist, not a killer” 60 Years in the Indiana

Department of Correction, Consecutive to California Sentences

ELKHART COUNTY COURTHOUSE

REFERENCES

Broun, K., Mosteller, R., and Giannelli, P. (2002) EVIDENCE: CASES AND MATERIALS (6th Ed.) St. Paul, MN: Thompson West.

Mott v. State (Ind. Ct. App. 11/13/08) (unpublished disposition).

United States Department of Justice (2002). “Using DNA to Solve Cold Cases.” Available online at http://www.ojp.usdoj.gov/nij/pubs-sum/194197.htm.

Special Thanks

Kenneth R. Martin, Esq., Goshen, Indiana

Curtis T. Hill, Elkhart County Prosecuting Attorney

Vicki E. Becker, Elkhart County Chief Deputy Prosecuting Attorney

Orchid Cellmark, Inc.