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Drug defendant awaits trial for homicide
McCoy was the subject of a ’21 SLANT bust, ’22 OWI crash that killed a Janesville woman
Mark D. McCoy
Mark D. McCoy

MONROE — Green County officials will continue prosecuting a Monroe man for allegedly running a major drug operation out of his house in a residential neighborhood, even though the suspect also faces reckless homicide charges in neighboring Rock County.

The defendant, Mark D. McCoy, 47, of Monroe, was among three people charged after an investigation — led by the State Line Area Narcotics (SLANT) team — involved a suspected marijuana grow operation in the 500 block of 21st Street on the city’s southwest side.

The two-story brick house was raided last February 10, 2022. In addition to the pot grow, and 17,000 grams of marijuana, authorities also allege in a statement that they uncovered separate psilocybin mushrooms grow operation — along with 50 grams of suspected cocaine and nearly 3 grams of heroin. There also was a separate grow operation in the garage at that location.

In that case, McCoy, was charged with maintaining a drug trafficking place, manufacturing THC, manufacturing psilocybin, possession of cocaine with intent to deliver, felony possession of a firearm, bail jumping and possession of drug paraphernalia. 

McCoy was out on a $50,000 signature bond on that drug case — and yet another from a 2021 traffic stop near Monroe — when authorities say he was driving and crossed the center line of South County Road D on the morning of April 23, 2023, and collided with a vehicle driven by 55-year-old Susan Hohmann of Janesville.

Hohmann was pronounced dead at the scene. 

“Mr. McCoy subsequently posted bail and was released from custody and at that time allegedly committed the (OWI) crimes in Rock County,” said Green County District Attorney Craig Nolen. “A trial is scheduled in January for (the 2022 drug case) and is proceeding irrespective of the Rock County charges.”

McCoy, who also lists a Janesville address, and has pleaded not guilty to the homicide by intoxicated use of a motor vehicle charge in Rock County, where he also is charged with felony bail jumping.

Nolen said all the suspects remain innocent until proven guilty in court.

Meanwhile, in a 2021 case — before the SLANT raid on his house — McCoy was clocked by Green County deputies going nearly 70 mph at about 3 a.m. on Wis. 11, with a passenger along.

The deputy smelled marijuana and a K9 later alerted that there were drugs in the car. 

A search turned up a loaded handgun, along with cocaine, methamphetamine, and marijuana. As a result, McCoy and a passenger were charged with multiple felonies. Nolen said the 2021 stop was separate from the SLANT case and that other evidence was developed to secure a warrant for the suspected drug house.

McCoy, who had an extensive criminal record in Wisconsin prior to the most recent arrests, remains in custody in Rock County jail awaiting his trials.

Also arrested in the SLANT bust was Tiffany J. Turner, 42, of Monroe. She was initially charged with maintaining a drug trafficking place, manufacturing THC, manufacturing psilocybin, possession of cocaine with intent to deliver, felony possession of a firearm, bail, and possession of drug paraphernalia.

In August, she pleaded guilty to a single count of maintaining a drug trafficking place and was sentenced to probation, according to court records. The other charges were dismissed by a judge but read into the court record.