MINNEAPOLIS (WCCO) — WCCO-TV has learned more about the Stillwater prison inmate accused of killing Corrections Officer Joseph Gomm.

Edward Muhammad Johnson is serving nearly 29 years for second-degree murder. The Minnesota Department of Corrections transferred him to the maximum-security prison in Oak Park Heights after Wednesday’s killing.

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Johnson’s criminal history begins with the murder in 2002 — but WCCO-TV has discovered that is not where it ends.

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“This inmate was actually convicted of assaulting a guard at Hennepin County Jail,” said DOC Commission Tom Roy.

In that case, Johnson struck a detention deputy that resulted in cut under his left eye.

Edward Muhammad Johnson in a 2003 mugshot (credit: MN DOC)

According to court documents, it happened while Johnson was awaiting trial for the 2002 murder of Brooke Thompson, a woman he lived with. A jury convicted him of stabbing her to death. Her 5-year-old daughter witnessed Johnson banging her head on the bathroom door the night before her body was found in the bathtub.

Once inside the prison system, Roy said Johnson has had trouble.

“The discipline record of this individual is significant. He has served about 1,700 days in segregation,” Roy said.

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But in 2004, it was Johnson at the center of a brutal attack in Stillwater prison, where he lost his right eye. He sued the DOC for failing to protect him from another inmate. A jury awarded him half a million dollars, most of which went to the family of his murder victim.

A source told WCCO-TV that Johnson had not been in separation or solitary confinement for two years.

A family member told WCCO-TV Thursday that Johnson’s parents were police officers who died in a murder-suicide in the late 80s, part of which he witnessed.

Wednesday’s murder happened in a place where inmates work in welding and carpentry. A source told WCCO-TV that Johnson used a hammer against Officer Gomm.

Roy explained why Johnson was allowed in the work program.

“We have an individual who for a length of time demonstrated relatively good behavior, and we have a limited pool of employees to draw from,” Roy said.

DOC officials acknowledge that there is a staffing shortage in the prison system, citing a national study from 2015 that found system-wide they are in need of at least 150 more corrections officers in Minnesota — and 27 officers in Stillwater alone. The DOC said it has presented this information to state lawmakers.

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Since 2011, Minnesota DOC has requested funding for 187 more prison officials. To date, they have only received funding for 15.