Randall Brown: Man stalks ex-GF and kills her BF after searching 'how to kill someone with a knife'

Warning: This article contains a recollection of crime and can be triggering to some, readers’ discretion advised.

FLORIDA, UNITED STATES: Randall Brown has been convicted of murdering his ex-girlfriend's boyfriend. In this incident, the 39-year-old man from Florida committed the crime by stabbing his ex-girlfriend's boyfriend 100 times at their residence and subsequently setting their house on fire.

During the investigation, authorities delved into Brown's work phone, discovering searches such as "how to kill someone with a knife" and other incriminating queries.

Additional details surrounding the motive for the murder of Kissy Mackey's boyfriend, perpetrated by Brown, emerged as investigators obtained information from Mackey's social media accounts.

Kissy Mackey identifies fire at her home and reports Police

The crime happened between 1 and 3 a.m. on August 3, 2021, when the victim and his girlfriend awoke at his home to the smell of gasoline and smoke and then saw the front door on fire, prosecutors said.

Kissy Mackey, the girlfriend, called 911 to report the stabbing and fire at 3 a.m., telling officers she and the victim heard a knock at the door and he was stabbed by an unknown suspect, who set the front door area of the apartment on fire. 

An autopsy found the victim had been stabbed over 100 times all over his body. Several wounds were deep and appeared to be consistent with the use of a larger-style knife, authorities said in the affidavit.

Mackey said the suspect then took off on a bicycle. She said she got into her vehicle, chased him, and ran him over. Blood was visible on the outside of her vehicle. She said she last saw him running and holding a gas can, which was later found in a rear yard. 

A search of trash cans nearby turned up a black backpack with a folding-style knife and a GPS tracking device.

Detective identifies Kissy Mackey’s social media accounts

The investigation took a significant turn when an anonymous individual contacted the police, reporting that Kissy Mackey had updated her "Facebook Relationship Status" to indicate she was now in a relationship with someone named "Randy Brown."

Upon inspection of Mackey's Facebook account, a detective noted the removal of the previous relationship status mentioning "Randy Brown" as her love interest.

Subsequently, while perusing "Randy Brown's" Facebook profile, the detective came across a photo of a Black male posing with a black/gray trimmed backpack resembling the one found in the trash can.

Two days after the homicide, on August 5, 2021, another caller identified "Randy Brown" on Facebook as Randall Bernard Brown, according to court documents. 

The informant informed detectives that Brown had reported a leg wound to his right upper thigh to his management and claimed to have seen Brown at work on the day of the murder, sweating profusely at 5:15 a.m.

Video footage emerges on Randall Brown’s investigation

Video footage confirmed Brown's presence at the business on the specified date and time. The footage showed Brown entering with a bag, proceeding to a closed room, and leaving with the bag.

The caller also mentioned Brown's unusual behavior that day, stating that Brown had disclosed his happiness about the victim's killing by unknown suspects.

In response to questions about his leg injury, Brown informed a co-worker that he had reported it as a workplace injury caused by glass. However, he provided inconsistent details about how and where the injury occurred.

Evidence linking Brown to a Dollar General store included bloody tissue/cotton dressing, first-aid materials, and a receipt found on an abandoned property. Surveillance footage from the store showed Brown purchasing these items, connecting him to the crime.

A tipster informed the police that Brown and Mackey had been together since the day of the homicide and bragged about their renewed relationship. 

Detectives later observed Brown and Mackey casually conversing in his driveway.

Confirmation that the GPS device found belonged to Brown came after investigators discovered it had pinged at Brown's home and the victim's residence on specific dates. 

Brown, under police questioning, admitted to driving Mackey near the victim's residence after the incident but denied driving to the victim's residence before the incident.

Further investigation revealed that Brown had placed the GPS device on Mackey's car after their breakup and had conducted incriminating searches just before the murder, according to prosecutors.

Prosecutors claimed, “Investigators with Jacksonville Sheriff’s Office discovered the girlfriend — Kissy Mackey — broke off her relationship with Brown a few weeks prior. Around the same time as the breakup, Mackey’s son died, and she told Brown she was about to be rich. Brown knew Mackey was already dating another man and he attempted to win her back. Brown put the tracking device on Mackey’s car to find out where she was sleeping at night. Just over a day before the murder, Brown searched on Google how to kill someone with a knife then made other incriminating searches before and after the murder. Mere hours after the crime, Mackey changed her Facebook status to ‘in a relationship’ with Brown" as per Law&Crime.

Brown is facing the possibility of the death penalty as prosecutors pursue the harshest punishment. Meanwhile, Mackey, who is undergoing a separate prosecution, faces charges of being an accessory after the fact, according to prosecutors.