Questions concerning DNA contamination were raised during Friday’s motions hearing in the Austin Sigg homicide case.

Sigg is accused of murdering 10-year-old Jessica Ridgeway in October 2012 in Westminster.

Last month he entered a not guilty plea, despite an alleged confession and the discovery of her remains in his home.

He faces life in prison with parole after 40 years.

According to the prosecution, a contamination memo does not mean contamination did in fact occur, it just means contamination was possible.

The 18-year-old’s defense team asked for documents from the Colorado Bureau of Investigation concerning DNA samples taken by bureau in the case.

According to the defense team, three contamination memos were produced Oct. 23-26, 2012, regarding DNA samples in two cases.

Two memos were connected to the DNA in the Jessica Ridgeway case, who was abducted and murdered last October, and one memo was connected to the Kentner Lake jogger case, in which Sigg is accused of attempting to kidnap a woman over Memorial Day weekend last year.

Sigg’s defense team filed a motion for validation of the DNA samples and a review of the machines used to test the samples.

The machines haven’t been reviewed since 2010, when CBI began using the machines, but regular maintenance is done and protocols of the machines are met daily.

CBI lab director Kathleen Fetherston testified during the hearing describing how the machines work and how DNA contamination is possible.

A second motions hearing is scheduled for 9 a.m. on June 21.