A former DeKalb County police officer was sentenced to 15 years in prison plus 10 years on probation after pleading guilty Monday to having sexual relationships with two teenage girls, both of them 15 at the time.

Judge Cynthia Becker told Quevius Thornton, 30, he had caused his victims irreparable harm and betrayed the trust of the public and his fellow police officers.

"I'm not in a position to forgive you," Becker said. "I'm appalled."

Thornton pleaded guilty to five felony counts of statutory rape and four counts each of enticing a child for indecent purposes and child molestation. He also pleaded guilty to three misdemeanor charges. The incidents took place in late 2010 and early 2011. He was arrested Jan. 5.

The family of one of the girls knew Thornton, a married father of two, and considered him a "mentor" to her," according to Anna Davis, an assistant district attorney.

"The victim wanted him to know how much he had changed her life," Davis said.

Now she is afraid of him, according to the prosecutor. She "trusted him because he was a police officer and he abused that trust for his own personal needs," Davis said.

Thornton tearfully apologized to his victims and their families. One of the girls left the courtroom sobbing.

According to the prosecutor, Thornton would have sexual encounters with the girls at his home, in parks and in parking lots. He also offered them marijuana he had seized from suspects, Davis said.

"The person who stands before you is not a bad guy," Thornton said. "I'm a good person who made a bad mistake ... I was a responsible adult and should have used better judgment. I have thrown away all my hard work and dreams. I have cried and cried ... about what I've done to myself and my victims. I take full responsibility."