Anthony Mungin v. State of Florida, 320 So.3d 624

Anthony Mungin was convicted of the 1990 first‑degree murder of a convenience‑store clerk and sentenced to death; conviction affirmed on direct appeal.
A bullet recovered from the victim was forensically linked to a .25‑caliber pistol found at Mungin’s residence. A customer later identified Mungin leaving the store soon after the shooting.
Deputy Malcolm Gillette testified at trial that he found a stolen car near Mungin’s arrest, saw two spent shell casings in the car, but his contemporaneous inventory form noted “nothing visible.”
In 2016 Gillette signed an affidavit stating he did not see shell casings and had not reviewed his paperwork before trial; Mungin filed a third successive Rule 3.851 motion in 2017 relying on that affidavit.
Mungin asserted Brady and Giglio claims (suppression/false testimony), ineffective assistance for failure to investigate/cross‑examine Gillette, and that Gillette’s affidavit was newly discovered evidence likely to produce acquittal.
The postconviction court held an evidentiary hearing, denied relief on the merits, and the Florida Supreme Court affirmed on the alternative ground that all claims were untimely and procedurally barred for lack of due diligence.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Timeliness / newly discovered‑evidence exception	Gillette’s 2016 affidavit is newly discovered; motion filed within a year of affidavit	Gillette was a known, available witness since trial; Mungin failed to show due diligence	Claims untimely and procedurally barred; affirm denial
Brady / Giglio (suppression / false testimony about casings)	State suppressed that Gillette saw no casings and permitted false testimony	Procedural bar; alternatively no reversible Brady/Giglio violation shown	Denied as procedurally barred (postconviction court had denied on merits)
Ineffective assistance for not contacting/cross‑examining Gillette	Counsel failed to investigate or cross‑examine Gillette about discrepancies	Claim untimely; no explanation why evidence could not have been discovered earlier	Denied as procedurally barred
Newly discovered evidence likely to produce acquittal	Gillette’s affidavit would undermine State’s case and likely produce acquittal on retrial	Evidence was discoverable earlier; Mungin did not exercise due diligence	Denied as procedurally barred

Mungin v. State, 689 So. 2d 1026 (Fla. 1995) (direct‑appeal opinion affirming conviction and sentence)
Reed v. State, 116 So. 3d 260 (Fla. 2013) (new‑evidence timeliness tied to discoverability and diligence)
Rivera v. State, 187 So. 3d 822 (Fla. 2015) (defendant bears burden to establish timeliness of successive claims)
Mills v. State, 684 So. 2d 801 (Fla. 1996) (lack of due diligence where witness was known to defense)
Jones v. State, 732 So. 2d 313 (Fla. 1999) (untimely claim must include sworn explanation for delay)
Applegate v. Barnett Bank, 377 So. 2d 1150 (Fla. 1979) (appellate review may affirm on any correct ground regardless of trial court reasoning)
Brady v. Maryland, 373 U.S. 83 (1963) (prosecutorial duty to disclose favorable, material evidence)
Giglio v. United States, 405 U.S. 150 (1972) (impeachment evidence and false testimony materiality standard)