Facts on Post-Conviction Relief for Newly Discovered Evidence of Innocence

Most wrongful convictions are not overturned with DNA evidence. Criminalists estimate that DNA
evidence is only probative in 5-10 percent of criminal cases. The National Registry of Exonerations reports
that 1,858 wrongfully convicted Americans have been exonerated; only 18 percent of those cases involved
DNA evidence.1

Wyoming’s current law has time barriers that make it very difficult for the wrongfully convicted to
prove their innocence with new, non-DNA evidence. Wyoming’s Rule 33 of Criminal Procedure requires
a movant to make a motion for a new trial based on newly discovered evidence before or within two years
after final judgment. W.S. §§ 7-14-101 to -108 allows a petition for relief based on violation of a
constitutional right within five years after entry of the judgment of conviction, but this doesn’t help in cases
with new evidence of innocence but no constitutional violation.

24% of proven wrongful conviction cases involved false or misleading forensic science. Advancements
in scientific knowledge and techniques continue to undermine conclusions about forensic evidence used in
criminal convictions. For example, two decades of fire research has debunked evidence that fire experts
once thought indicated arson2 and flaws have been revealed in forensic analysis and testimony comparing
bitemarks, hair, bullets and other pattern evidence.
It often takes years of research, studies and reviews for flaws in forensic analysis to be revealed and new
accepted standards to emerge. Wyoming’s absolute 2-year time limit for a defendant to present newly
discovered evidence is a barrier to justice for individuals who were wrongfully convicted based on
misapplied science.
How does Wyoming compare to other states?
Wyoming is one of only three states with an absolute time restriction on when newly discovered evidence
may be introduced after the trial verdict or final judgment. The other states are Arkansas and Idaho.
29 states have no time limit for when a petitioner can introduce newly discovered evidence of innocence postconviction (AK, AZ, CA, CT, CO, HI, IL, IN, IA, KS, MD, MA, MI, MO, NV, NH, NJ, NM, NY, NC, OK, RI,
TX, UT, VA, VT, WA, WV, WI).
12 states have time limits with due diligence exceptions for introducing newly discovered evidence in postconviction proceedings, meaning that there may be a time limit for introducing new evidence, but there is an
exception to the time limit if the evidence could not have been discovered with due diligence. (AL, FL, GA, IL,
KY, LA, MN, MS, MT, NE, OH, OR).
Nebraska and California recently changed their laws to better ensure that wrongfully convicted people can
prove their innocence with newly discovered non-DNA evidence.
National Registry of Exonerations.
In 1992, the National Fire Protection Association (“NFPA”) published NFPA 921, a “Guide for Fire and Explosive
Investigation,” which set the standards for arson investigations. NFPA 921 found no scientific basis for previous claims by fire
experts that certain factors were evidence of arson. Therefore numerous arson investigations and convictions prior to the mid1990s, when NFPA 921 was widely accepted, may have relied on erroneous science.
1
2