John McMahon did not set out to be a police sketch artist.
"It was pure chance," he said. A road deputy, he was doodling faces on a breakfast placemat at a cafe one morning in 1979.
A homicide detective spotted his talent, and had him turn a witness's description into a wanted man's picture. It netted an arrest.
"I have to admit I was stunned," he said. McMahon traded his pistol for a pencil – for good.
"I've had over 1,000 arrests based on my sketches over the past 30 years,” said McMahon, with the Broward Sheriff’s Office.
McMahon's artistry is low tech. It begins with a blank sheet of paper. He asks a witness to picture the face of a robber or attacker, someone they saw in a violent moment.
"Maybe [it happened in] three minutes, maybe a split second, maybe two minutes, maybe through duct tape," said McMahon. "Maybe with a gun to their face.”
Still, he insists the recall is not difficult. "Your brain is like a computer," McMahon explained. "There's a picture inside of your mind."
One store clerk remembers a young man and woman who both pointed a gun at him the night of Oct. 12 at a Family Dollar store in Broward. They demanded he open the cash register.
"The boy ordered the girl to shoot me," said the clerk. At that moment, surveillance video shows him yank the young gunwoman over the counter. He intended to use her as a shield from her accomplice, he said. The clerk dodged two gunshots from her, as her cohort dashed out the door. Moments later, she ran away too.
McMahon asked the clerk to describe the male gunman, who appears less on surveillance video than his female companion. McMahon and the clerk scrolled through a few hundred mug shots on a computer screen.
"This is not a lineup," McMahon said. "We're just looking for people that I can use their facial characteristics that highly resemble the suspect."
The clerk pointed to eyes and face shapes for a place to begin.
"The eyes are the most important part of it," said McMahon. "If the eyes aren't done properly, it throws the whole drawing off."
With each feature, he took new input from the clerk.
"The chin, you feel comfortable with the chin?" McMahon asked, with a nod from the clerk in return.
It can take up to five hours for McMahon to get the shading and lines just right.
There's no mistaking his skill. The resemblance between his sketches and actual mug shots of suspects he helped catch is unmistakable.
One sketch from January of this year helped someone recognize a man accused of sexually assaulting two girls at a Wilton Manors children's shelter. Police arrested him on a cruise ship, and the case is now pending in court.
As for the sketch from the Family Dollar store holdup, the clerk is pleased with how well McMahon's creation matches his memory of the gunman.
"It looks just like him," he said, almost sounding surprised. Now it will be shared with media outlets in hopes of jogging someone's memory.
McMahon says his sketches prove to the store clerk and other victims that "they've done something to fight back."
Below: McMahon's sketch of the gunman in the Family Dollar incident.
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