A Mableton man was sentenced Tuesday to 40 years in prison for murdering his girlfriend.

Thomas Leonardo Schwartz, 47, pleaded guilty to voluntary manslaughter and aggravated assault Monday.

Schwartz admitted to shooting his girlfriend Janice Oates, 45, in the head in July of last year, according to the Cobb district attorney’s office.

According to sentencing guidelines Schwartz will have to serve every one of the first 20 years in prison before being eligible for parole.

As part of his plea deal, a judge dismissed an earlier possession of a firearm charge.