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Forensic Evidence


"Changed Science" Statutes

Six states have enacted so-called "changed science" statutes. The Innocence Project has summarized them.



Valena Beety, "Changed Science Writs and State Habeas Relief" - 2020

This article reviews the growth of state-level changed science writs and examines how other states can adopt this tool to review habeas petitions based on scientific evidence. This Article posits that changed science writes both incentivize greater reliability of evidence at trial by creating a process of review, and help to identify wrongful convictions based on inaccurate, misrepresented, or faulty scientific evidence. 


Simon A Cole, Changed Science Statutes: Can Courts Accommodate Accelerating Forensic Scientific and Technological Change?" - 2017

In the past several years, the nation's two most populous states have passed new statutes specifically intended to address the issue of rapidly changing scientific and technological knowledge, perhaps signaling a national trend. This reflection article situates a discussion of these "changed science statutes" within a sociological understanding of the nature of scientific knowledge, exploring the question of what it means for scientific knowledge to "change." It then traces the procedural history of the two cases wildey credited with prompting the passage of the statutes and courts' varying interpretations of the statutes. It suggests that, while changed science statutes offer broad potential for redressing the use of impunged science in closed cases, courts have thus far limited their applicability through narrow interpretation of the statutes.


Post-conviction fingerprint/ballistic database access statutes


Although all 50 states have statutes enabling some form of access to post-conviction DNA database searching, only 5 states (Arizona, Arkansas, Idaho, Illinois, and Minnesota) extend that right to other kinds of forensic databases (such as fingerprint and ballistics).

Nine people have been exonerated in part because they were able to conduct post-conviction fingerprint database searches, and Patrick Pursley was exonerated in part because of a post-conviction ballistics database search.

In this op-ed, Registry Director Simon Cole and Innocence Project Co-Founder Barry Scheck argue in favor of a right to post-conviction searching of all forensic databases. They write about that issue, and others, in:


Simon A. Cole & Barry C. Scheck, Fingerprints and Miscarriages of Justice: 'Other' Types of Error and a Post-Conviction Right to Database Searching - 5 July 2018 

Much of what has been written about the role of friction ridge (“fingerprint”) evidence and miscarriages of justice has focused, understandably, on erroneous identifications, cases in which a crime scene print is erroneously attributed to a suspect (or, more rarely, a victim). This Article, co-written by Registry Director Simon Cole, undertakes a systematic and comprehensive examination of “other” types of error in friction ridge analysis and how they can, and have, contributed to miscarriages of justice. These errors include “missed identifications” and well as “missed exclusions.” Read more.


General Studies of Forensic Evidence and Wrongful Conviction


Catherine L. Bonventre, Wrongful convictions and forensic science - 18 October 2020

More than 2,600 exonerations have been documented in the United States since 1989. Forensic science—in the form of postconviction DNA testing—has played a critical role in the revelation that wrongful convictions are a problematic feature of criminal justice. Yet, forensic science is also among the many factors—including eyewitness misidentification, false confessions, informants, and more—that are correlates of wrongful convictions. Forensic science contributes to erroneous convictions when analysts provide invalid testimony at trial or when such evidence fails to correct false crime theories. Moreover, while intentional forensic misconduct certainly exists, the effects of confirmation biases may present a greater threat to forensic analyses. The preceding mechanisms and reform efforts are discussed. Read More.


Vanessa Meterko, Strengths and Limitations of Forensic Science: What DNA Exonerations Have Taught Us and Where to Go From Here - December 2016 

The criminal justice system has historically accepted forensic science testimony with great deference and trust. After all, scientists are intellectually curious experts with specialized training who make dispassionate observations about the laws of nature. However, over the past 25 years, post-conviction deoxyribonucleic acid ("DNA") testing has revealed the limitations of scientific evidence by conclusively proving innocence in cases in which forensic analysts had previously presented evidence of guilt. In this way, DNA exoneration cases have prompted a more critical evaluation of forensic science in general. Read more.


Simon A. Cole, Forensic Science and Wrongful Convictions: From Exposer to Contributor to Corrector - June 6, 2012

Brandon Garrett's book, Convicting the Innocent, makes a number of important contributions to the scholarly and public discourse on miscarriages of justice. In this essay, I will focus on the contribution that is most related to my own reserarch interests: its contribution to our understanding of the relationship between forensic science and miscarriages of justice. Read more.


Brandon L. Garrett & Peter Neufeld, Invalid Forensic Science Testimony and Wrongful Convictions - March 2009 

This is the first study to explore the forensic science testimony by prosecution experts in the trials of innocent persons, all convicted of serious crimes, who were later exonerated by post-conviction DNA testing. Trial transcripts were sought for all 156 exonerees identified as having trial testimony by forensic analysts, of which 137 were located and reviewed. These trials most commonly included testimony concerning serological analysis and microscopic hair comparison, but some included bite mark, shoe print, soil, fiber, and fingerprint comparisons, and several included DNA testing. Read more.