Fair Trial Analysis addressed a question at the center of William Thomas “Tommy” Zeigler’s appeal: how would a jury evaluate the case with evidence unavailable at his original trial? Our research estimated an 86.3% probability of acquittal in a retrial that included newly discovered DNA evidence.
On July 9, 2026, Barry C. Edwards, J.D., Ph.D., and Fair Trial Analysis, Inc., presented the study to the Florida Supreme Court in an amicus brief supporting Zeigler’s appeal. The brief explained our findings, how we produced the estimates, and how empirical research could assist the Court in applying Florida’s standard for a new trial.
The case and the new evidence
On Christmas Eve 1975, four people were killed at Zeigler’s furniture store in Winter Garden, Florida: his wife, Eunice; her parents, Perry and Virginia Edwards; and Charles Mays. Zeigler was also shot. Prosecutors argued that he planned the killings to collect life-insurance proceeds and make the crime appear to be a robbery. Zeigler maintained that he encountered a robbery and fought for his life. He was convicted in 1976 and sentenced to death after the judge overrode the jury’s recommendation of life imprisonment.
Decades later, advanced DNA testing supplied information unavailable to the original jury. Testing identified Mays’s blood on Zeigler’s clothing and substantial amounts of Perry Edwards’s DNA on Mays’s pants. It did not identify Eunice’s or Virginia’s DNA on Zeigler’s clothing. Small amounts of Perry’s DNA were found in two bloodstains on Zeigler’s shoes, mixed with Mays’s blood.
The defense argued that these findings undermined the prosecution’s account of Zeigler’s violent struggle with Perry and supported Zeigler’s account of an encounter with Mays. The State disputed their exculpatory significance, arguing that Mays’s blood on Zeigler’s clothing was consistent with Zeigler killing him. The DNA results did not establish the order of the killings.
What Florida’s standard requires
Under Florida’s Jones standard, newly discovered evidence must satisfy two requirements: it must have been unknown at trial and undiscoverable through due diligence, and it must be sufficiently consequential that it would probably produce an acquittal on retrial. Courts evaluate the new admissible evidence together with the evidence already presented.
FTA focused on the second requirement. Applying it requires a prediction about a future jury’s decision. Our study translated that question into a measurable proposition: whether the probability of acquittal with the new evidence exceeded 50%. That numerical formulation was FTA’s research approach to the legal question.
How we studied the question
Barry Edwards designed and conducted an online survey experiment from July 2–5, 2026. The analysis included 241 Florida adults who met the study’s capital-jury qualification criteria. Statistical weights adjusted the sample toward Orange County’s demographic profile, including age, education, race, ethnicity, gender, and income.
Participants were randomly assigned to read one of three versions of the case:
- The original trial evidence.
- The original evidence plus the newly discovered DNA findings.
- The original evidence plus the DNA findings and additional investigation evidence, including information about an attempted robbery nearby.
The summaries drew on court opinions, the trial court’s order, and associated briefing. Participants voted guilty or not guilty, then considered a different evidentiary version and voted again. This design allowed comparisons both across participants and within the same participant’s responses.
The survey measured individual verdict preferences. FTA then used a mathematical model of jury selection and deliberation to translate those preferences into estimated jury verdict probabilities. The analysis specified a twelve-person jury and ten peremptory challenges for each side.
What FTA found
The new DNA evidence substantially increased support for acquittal.
| Evidence considered | Individual support for acquittal | Probability of jury acquittal |
|---|---|---|
| Original trial evidence | 44.6% | 52.7% |
| Original evidence plus DNA findings | 62.8% | 86.3% |
| Original evidence plus DNA and additional investigation evidence | 63.8% | 87.6% |
The estimated probability of acquittal with the DNA evidence was 86.3%, with a reported margin of error of 8.2 percentage points. With the additional investigation evidence, the estimate was 87.6%, with a margin of error of 7.5 percentage points.
Compared with the original trial condition, the DNA evidence increased the estimated probability of acquittal by approximately 33.6 percentage points.
Bringing the research to court
Attorney Bailey Howard filed the amicus brief on behalf of Edwards and FTA in Zeigler v. State, Florida Supreme Court case SC2026-0617. As amici—friends of the court—we offered the research to assist the Court’s legal judgment.
The brief supplied the study design, results, figures, and explanation of the statistical model. The survey instrument, datasets, and replication code were made available so others could examine the methods and reproduce the analysis.
Our findings supported the conclusion that acquittal would be probable in a retrial with the new DNA evidence. The brief presented those findings as an empirical resource for the Court, leaving the ultimate decision about relief to the justices.