A former Denver police officer was sentenced Thursday to four years of probation for possession of child pornography.

Timothy J. Kelley, 50, received a four-year deferred sentence Thursday in Adams County District Court after pleading guilty on April 2 to sexual exploitation of child, a felony, according to court records.

Kelley, now a registered sex offender, is participating in a group treatment program, said Sue Lindsay, an Adams County District Attorney’s spokeswoman.

An investigation, by the Douglas County Sheriff’s Office, began in January 2014. Police served a search warrant on his Westminster home in May and seven child porn videos were found on a computer.

Kelley, who had been a Denver police officer since 1995, resigned shortly after the department became aware of the investigation. He worked for years as a crime scene investigator, but before his arrest he was a patrol officer in the Montbello neighborhood.

As part of the deferred sentence Kelley must stay out of trouble for four years, as well as meet probationary requirements, including treatment and counseling. He was ordered to pay fines and fees of $5,638.50, according to court records.

Kieran Nicholson: 303-954-1822, knicholson@denverpost.com or twitter.com/kierannicholson