Meryl S. McDonald v. State of Florida, 296 So.3d 382

Meryl S. McDonald, a death‑sentenced inmate, filed a fourth postconviction motion under Fla. R. Crim. P. 3.851 based on a 2014 DOJ letter criticizing portions of an FBI forensic hair analyst’s testimony at McDonald’s 1995 joint trial with Robert Gordon.
McDonald asserted Giglio (impeachment) and newly discovered evidence claims arising from the DOJ letter.
The circuit court denied the motion summarily without an evidentiary hearing; the Florida Supreme Court reviews such denials for legal insufficiency or when allegations are conclusively refuted by the record.
The Court treated the Giglio claim as substantially identical to one previously rejected in Gordon and held the prosecutor could not be required to cure alleged false testimony based on a letter issued roughly twenty years after trial.
The Court found the DOJ letter did not materially undermine the hair‑comparison evidence because (a) the trial testimony already included limiting language and cross‑examination about the limits of hair identification, (b) hair‑comparison science was not discredited, and (c) other admissible evidence (sweatshirt, shoes/prints, blood/DNA issues) would remain on retrial.
Because the letter would not likely produce an acquittal on retrial, the Court affirmed the summary denial of both the Giglio and newly discovered evidence claims.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the 2014 DOJ letter establishes a Giglio violation requiring relief	McDonald: DOJ letter shows FBI analyst overstated certainty and constitutes undisclosed impeachment material that undermines trial testimony	State: Letter postdates trial by ~20 years; prosecutor could not correct alleged false testimony based on information not available at trial; prior rulings reject similar claims	Denied — Giglio claim misplaced; summary denial affirmed
Whether the 2014 letter is newly discovered evidence warranting a new trial	McDonald: Letter reveals substantive problems with hair‑comparison testimony that would probably produce acquittal on retrial	State: Trial record already contained limiting testimony and cross‑examination; hair science not discredited; other strong evidence links McDonald to the crime	Denied — Letter would not probably produce acquittal; summary denial affirmed

Giglio v. United States, 405 U.S. 150 (1972) (prosecutor must disclose impeachment evidence and cannot use known false testimony)
Wyatt v. State, 71 So. 3d 86 (Fla. 2011) (limitations on posttrial impeachment claims when evidence arises long after trial)
Jones v. State, 709 So. 2d 512 (Fla. 1998) (standard for newly discovered evidence requiring probable acquittal on retrial)
Gordon v. State, 704 So. 2d 107 (Fla. 1997) (trial facts tying defendant to crime; precedent relied on in related postconviction litigation)
Duckett v. State, 148 So. 3d 1163 (Fla. 2014) (overstated hair‑analysis testimony, when read in full context, did not create reasonable doubt)
Mungin v. State, 79 So. 3d 726 (Fla. 2011) (standards for affirming summary denials of postconviction motions)
Darling v. State, 45 So. 3d 444 (Fla. 2010) (same)
McDonald v. State, 117 So. 3d 412 (Fla. 2013) (prior postconviction challenges to bloodstain and DNA analysis in McDonald’s case)