A 47-year-old prison inmate has taken a rare step in court and is not contesting the first-degree-murder charge against him for killing a fellow prisoner at the Macomb Correctional Facility.

Michael Ketchum, who is already serving 44 years for trying to kill another inmate, entered a no-contest plea Monday in Macomb County Circuit Court in Mount Clemens for the 2022 slaying of Ruben Martinez, 28, and will be sentenced April 23 to life without parole by Judge Kathryn Viviano, according to court records.

As part of a plea deal, charges of attempting to kill another inmate the same day and possession of a weapon in prison will be dismissed, records say.

There have been only a handful of first-degree murder pleas in Macomb County over the past 20 years.

The slaying was discovered Oct. 18, 2022 at the Lenox Township state prison after Ketchum stabbed another inmate eight times in the head and neck while on the way back to his cell after breakfast, according to authorities. Officers discovered Ketchum’s cellmate, Martinez, hogtied, strangled and stabbed to death underneath his bed in his cell, officials said.

A sharpened object was used as a weapon in the attack, officials said.

Officials did not provide a motive.

It was the third murder and one of four incidents at the 26 Mile Road facility in 2022 that resulted in the warden being removed by the Michigan Department of Corrections. MDOC officials learned in late November 2022 that a rap video was filmed the prior September in the prison and shown on youtube.com. Cameras and cell phones are banned for inmates.

In May 2022, Elrick Cooper fatally stabbed Martell Smith, 26, with a shank during a fight. Cooper pleaded no contest to second-degree murder last December and was sentenced Jan. 30 to 8-½ to 20 years by Macomb Circuit Judge Richard Caretti. The sentence was consecutive to a 25-to-50-year term Cooper is serving for a 2007 armed robbery in Saginaw County.

Another slaying occurred in September 2022 when Michael Anthony Fleming, 41, fatally stabbed inmate Christopher Neely, 33. Fleming was charged with first-degree murder and pleaded no contest to second-degree murder in 2023 as part of a deal to also dismiss fourth-habitual status. He was sentenced in November 2023 by Macomb Circuit Judge Julie Gatti to 15 to 50 years in prison, to be served consecutively to his 25-to-50-year term for three counts of first-degree criminal sexual conduct in Saginaw County in 2009.

Ketchum, meanwhile, was convicted of attempted murder and sentenced to 44 years in prison in 2021 for attacking a prisoner in a Saginaw County facility, according to prison records.

At that time, he was serving 28 years for a 2009 attempted murder in Kalamazoo County, records say. He also received lesser sentences for kidnapping, armed robbery and operating a methamphetamine lab in two additional incidents that year in Kalamazoo County, records say.

Ketchum in 2019 also attacked a fellow prisoner in Saginaw County, records say.