
Left to right: Frank Kennedy and Anthony Mistretta (St. Mary’s Police Department).
Two Georgia men will spend the rest of their lives behind bars for the horrific murder of a homeless man found beaten, hog-tied, and anchored to the bottom of a lake, authorities announced this week.
In July 2023, John Andrew Mamph was all of 29 years old and living at an encampment in St. Mary’s — a small town located just north of the border with Florida — when he was attacked in a remote area known to locals as “Gilligan’s Island.”
During the attack, a large group of at least three and as many as four people took part in the beating, Peach State authorities allege.
“The defendants then transported Mamph to a nearby boat ramp where they put him in a boat and took him out on a lake,” the Brunswick Judicial Circuit District Attorney said in a press release. “While Mamph was still tied up, the defendants then weighed him down with multiple weights and dumped him into the lake so he would drown.”
Earlier this month, Frank Kennedy, 56, and Anthony Mistretta, 29, were convicted by a jury over their roles in Mamph’s murder.
In sum, the defendants were each convicted of one count of malice murder, felony murder, false imprisonment, kidnapping, and battery over the brutal slaying. Kennedy was also convicted of aggravated assault.
The pair were immediately sentenced after being convicted.
Mamph’s body was found sometime after noon the day following his murder by a local citizen who was jet-skiing with his family.
“The citizen observed the submerged body of Mr. Mamph in the clear water, returned to shore, and called 911,” prosecutors said.
The find was grim.
In a sense, the man’s body was not hidden, but rather, paraded.
Mamph was found tied to a cinder block at the bottom of the lake near an “aluminum roof flashing and also a black bag full of rocks tied together,” according to a police report obtained by Jacksonville, Florida-based NBC affiliate WTLV and Orange Park, Florida-based ABC affiliate WJXX, who collectively broadcast as First Coast News.
In comments to police, the man who found the body said he could “smell death” as he approached the victim, First Coast News reported.
That same night, a task force of local, county, and state law enforcement made their first arrests “based on eyewitness statements of the horrific crimes,” prosecutors said.
A total of five people were charged in relation to the murder.
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Before Kennedy and Mistretta went to trial, all the other defendants pleaded guilty.
Debra Leane Dougherty, 38, pleaded guilty to one count of felony murder and was sentenced to life in prison with the possibility of parole after serving at least 30 years.
Bernice Rose McGuire, 27, pleaded guilty to one count of conspiracy to commit aggravated assault and is awaiting sentencing.
The least culpable of the quintet, Megan Leigh Robison, 34, initially lied to law enforcement about what she knew after the fact about Mamph’s murder; she eventually pleaded guilty to one count of making a false statement and was sentenced to five years of probation.