SOUTH LAKE TAHOE, Calif. -

A man convicted of killing three teenager girls in the 1980s has been sentenced to death, the Monterey County District Attorney's Office said.

Joseph Michael Nissensohn was found guilty of three first-degree murder charges in October 2013 by an El Dorado County jury.

Those included the 1981 murder of 13-year-old Tammy Jarschke and 14-year-old Tanya Jones in the Carmel Valley. It also included the 1989 murder of 15-year-old Kathy Graves in South Lake Tahoe.

Jurors also found true additional special circumstances allegations, including a 1989 murder of Sally Joe Tsaggaris in Washington state.

The guilt phase of the trial started with jury selection more than 13 months ago in May 2013.

Nissensohn was convicted of the Washington murder in 1991 and was due to be released at the end of his sentence in 2008. At that time, in agreement with the Monterey County District Attorney’s Office, the El Dorado County District Attorney’s Office consolidated all three murders to be tried at the same time.