Hennepin County prosecutors allege that a convicted murderer ordered the beatings of witnesses so they would recant their trial testimony against him.
They also say 24-year-old gang member Lamonte Rydell Martin and his alleged accomplices, including his own mother, tried to bribe the witnesses in exchange for their signed affidavits.
Prosecutors are charging 10 people in a case that they describe as unusually complex.
Hennepin County Attorney Mike Freeman says "it's bad enough" to shoot someone to death, a crime that resulted in Martin's life sentence in prison.
"But once you get there, you scheme and try to figure out how you're going to intimidate the witnesses who gave honest testimony, you try to bribe them, you're beating them up while they're in prison, and you're intimidating their family elsewhere," Freeman said. "This kind of goes to corruption of the entire system."
Investigators with the Minneapolis police and the state Department of Corrections worked on the case for two years.