On Thursday, jurors in West Palm Beach convicted John McKenzie of raping a Boca Raton woman in 1989. Later that day, police announced they have tied McKenzie to another cold case rape in their city -- this one from 1987.
Investigators say they are searching through other unsolved sexual batteries to see if McKenzie is responsible.
For years, McKenzie appeared to be a successful businessman, working in Boca Raton and living on a sizable piece of property in Boynton Beach.
But according to Boca Raton Police and to DNA, McKenzie hid a dark secret about a violent past.
Jurors convicted McKenzie on Thursday of the 1989 rape, saying that he walked into a woman's apartment with a knife and raped her. The case went unsolved for decades until a DNA match brought police to McKenzie's door.
The victim told me in September that she was looking forward to the day McKenzie was punished for what he did. He will be sentenced later this month.
"I don't live in fear," she said. "I just knew that someday something good would come out of this."
A second DNA match in a 1987 case has again shone the spotlight on McKenzie. In that case, an attacker broke into a woman's apartment through a bedroom window while she slept, covered her face with a towel, helped himself to a wine cooler and sexually assaulted her.
After the attack, the victim -- who now lives in Hollywood, according to a police report -- gave police clothing and a wash cloth that contained evidence.
Now, McKenzie faces another charge of armed sexual battery along with a charge armed burglary for allegedly stealing a gold necklace from the victim's jewelry box.
Boca Raton Police Spokesperson Sandra Boonenberg called the arrest "gratifying."
"(Detectives) have been aggressively pursuing this," she said. "The technology for DNA has come so far. It speaks to the police work we did in 1987 and 1989."
Boonenberg said the case proves you can't trust anyone.
"It's frightening. You really don't know who people are," she said.
At the time of McKenzie's arrest in September for the 1989 case, I reported that police said McKenzie has a lengthy criminal history including arrests for rape, kidnapping, child abuse, theft, fraud and carrying a concealed weapon.
We learned McKenzie was sentenced to 5 years probation in 2010 on the concealed firearm charge.
The Illinois Department of Corrections said McKenzie was sentenced in 1978 to 20 years for rape, aggravated kidnapping and taking indecent liberties with a child. He didn't serve nearly that long in prison, but Illinois authorities said their files do not reflect why. He was sentenced again in 1985 to 2 1/2 years for child pornography. He left the Illinois Prison System in October of 1987.
According to an article in the Chicago Tribune from 1985, "A task force of local, state and federal agents investigating child pornography in the Chicago area Thursday charged a Bolingbrook man with being a major trafficker of pictures depicting boys in sexual acts. John McKenzie, 36, was arrested after he allegedly displayed some of the photographs at a meeting with undercover agents, said Jeremy Margolis, Illinois inspector general. Margolis said authorities seized more such photos and "a huge cache of child pornography records for adult customers" in McKenzie's apartment..."
McKenzie was a well-respected professional working in Boca Raton since 1987. An employee at Beacon Property Management confirmed that McKenzie was president at the company.
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