By Mason, Sage, and Tucker

All of the people previously featured were convicted of heinous felonies including homicide and rape. They all spent at least a decade in prison before they were exonerated by new DNA technology. They were all sentenced to life, and in some cases multiple life sentences or death row. They were all convicted by false eyewitness, faulty DNA evidence, or coerced confession.

About How Long Has Forensics Existed as a Science? 50 Years 100 Years 200 Years 500 Years 1000 Years Since Dinosaurs Roamed the Earth.

About How Long Has Forensics Existed as a Science? 50 Years 100 Years 200 Years 500 Years 1000 Years Since Dinosaurs Roamed the Earth.

1800s Brief Forensic History First Use of Toxicology Testing for Arsenic 1800s First Bullet Comparison To Capture a Murderer First use of Handwriting Documentation in Court First Use of Chemical Tests for the Presence of Blood First use of Fingerprints to Catch a Criminal

1900s DNA Testing Did not Become Popular Until the 1980s. Brief Forensic History DNA Testing Did not Become Popular Until the 1980s. First Use of Voice Analysis Development of the Chemiluminescent Reagent Luminol as a Presumptive Test for Blood Breathalyzers! 1900s First Use of Head-Space Analysis to solve an Arson Case

Project Innocence

Project Innocence

Project Innocence

Project Innocence

In March 1984, Dennis Maher was convicted of the assault and rape of two women in Lowell, Massachusetts. In April 1984, Dennis Maher was found guilty of the rape and assault of a third woman. Dennis Maher was sentenced to life without parole. He was detained in the Bridgewater State Hospital.

He Was Innocent After serving 19 years in prison, Dennis was exonerated in 2003 when semen samples taken from the original crime scene were used to exclude him from the list of possible suspects.

How Does DNA Testing Work? RFLP (Restriction Fragment Length Polymorphism) PCR (Polymerase Chain Reaction) STR (Short Tandem Repeat) Analysis Mitochondrial DNA Analysis DNA Profiling (Fingerprinting)

RFLP (Restriction Fragment Length Polymorphism) Refers to a difference in two or more samples of homologous DNA molecules arising from differing locations of restriction sites, and to a technique by which these segments are distinguished. Analysis technique was cheap enough to enjoy widespread application. Played an integral role in the progression DNA forensics, however, in several court cases the admissibility of RFLP evidence was questioned. Less prone to error than PCR, but has been largely replaced by PCR because PCR testing is faster.

RFLP Technique DNA cut into fragments using an enzyme. Cut DNA is put on a Gel material. Electrical current is applied to the Gel. DNA is negatively charged and fragments move towards the positively charged side. Smaller fragments move faster, and there is a separation of fragment length.

RFLP Technique

STR (Short Tandem Repeat) Analysis Used to compare loci on DNA from two or more samples. Consists of a microsatellite of a unit of two to thirteen nucleotides repeated hundreds of times. Measures the number of repeating units. Unlike RFLP, STR does not cut the DNA, rather probes are attached at the desired regions of the DNA and PCR is used to discover the lengths of the repeats. Very accurate, a 13- loci match in DNA has a 1:1billion likelihood.

The Polymerase Chain Reaction (PCR) PCR is a way to copy a piece of DNA thousands to millions of times. Fast and relatively easy Creates a much larger DNA sample to work with

How PCR Works All reactants are mixed together in a vial. The mixture is heated to 90-95 degrees Celsius for 30 seconds.

How PCR Works The mixture is cooled to 55-60 degrees Celsius. The temperature is heated again to 75 degrees Celsius

What’s Next? DNA must be visualized. Gel electrophoresis is used. Negative electrical charge repels negatively charged DNA. Smaller fragments of DNA are able to move further through the gel.

Genetic Fingerprint Comparison Bands of DNA in the gel are compared to bands from each suspect. Matching patterns of bands reveal a genetic fingerprint match

Mitochondrial DNA Analysis Uses DNA taken from the mitochondria instead of the nucleus. Can be used on old samples that may not have nuclear DNA left. Particularly useful in missing person’s cases since a child’s Mitochondrial DNA will be identical to the parent.

DNA Profiling Refers to the series of techniques used to interpret DNA information. First used in a criminal case by Sir Alec Jeffreys Used to convict 21 year old Colin Pitchfork of the rape and murder of two 15 year old girls. Before Pitchfork, the primary suspect was 17 year old Richard Buckland who had learning disabilities and confessed to the murder.

CODIS and AFIS Short for Combined DNA Index System and Automated Fingerprint Identification System. Contain the DNA and fingerprint information for around 10 million convicted and suspected criminals. DNA evidence is useless without something to compare it to. Because of laws, acquiring DNA samples from suspects can sometimes be difficult, and just because a DNA sample is acquired from a crime scene does not mean that a match will be found.

References Calandro, L., Reeder, D., & Cormier, K. (2005, January 6). Evolution of DNA Evidence for Crime Solving - A Judicial and Legislative History. Retrieved June 25, 2015, from http://www.forensicmag. com/articles/2005/01/evolution-dna-evidence-crime-solving-judicial-and-legislative-history Davis, C. (2015, March 11). Polymerase Chain Reaction: PCR Facts on Test and Steps. Retrieved June 25, 2015, from http://www.emedicinehealth.com/pcr_polymerase_chain_reaction_test/article_em.htm Dennis Maher - New England Innocence Project. (2011, February 8). Retrieved June 25, 2015, from http://www.newenglandinnocence.org/exonerees/dennis-maher/ Elvidge, S. (2015, June 8). Forensic Cases: Colin Pitchfork, First Exoneration Through DNA. Retrieved June 25, 2015, from http://www.exploreforensics.co.uk/forenisc-cases-colin-pitchfork-first-exoneration-through-dna.html Forensic Science History. (n.d.). Retrieved June 25, 2015, from https://www.troopers.ny.gov/Crime_Laboratory_System/History/Forensic_Science_History/ Kilpatrick, R. (n.d.). History of DNA profiling. Retrieved June 25, 2015, from http://www2.le.ac.uk/departments/emfpu /genetics/explained/profiling-history Murnaghan, I. (2014, October 25). Mitochondrial DNA Analysis. Retrieved June 25, 2015, from http://www.exploredna.co.uk/mitochondrial-dna-analysis.html Riley, D. (2005, April 6). STRs . Retrieved June 25, 2015, from http://www.scientific.org/tutorials/articles/riley/riley.html