A man once sentenced to death for the 1977 murder of a Brentwood teenager has died in prison.

Gregory Bowman was convicted of kidnapping, raping, and killing 16-year-old Velda Joy Rumfelt. His death sentence was set aside in 2011 after the state Supreme Court ruled jurors improperly heard information about two Illinois murders Bowman had been sentenced to life for. He was set free in those cases after a court threw out his confession.

Prosecutors as recently as last year were pursuing a new penalty phase against Bowman, intending to again seek the death penalty. DNA evidence linked him to Rumfelt’s murder.

Bowman, 64, was reported last year to be terminally ill. The Department of Corrections says his death appears to be due to natural causes.