Teenager Found Guilty Of Murdering Teacher

A Massachusetts teenager has been convicted of raping and killing his high school math teacher.

Philip Chism was convicted Tuesday in the 2013 slaying of Colleen Ritzer, a 24-year-old algebra teacher at Danvers High School, about 25 miles north of Boston.

Chism was 14 when he followed Ritzer into a school bathroom, strangled her, stabbed her at least 16 times with a box cutter and raped her. Ritzer's body was found in woods near the school.

Chism, now 16, was tried as an adult.

Chism's lawyer admitted his client killed Ritzer, but said he was suffering from severe mental illness and wasn't criminally responsible for his actions. A psychiatrist testifying for the defense said Chism was in the midst of a psychotic episode when he killed Ritzer. (Associated Press)