TELLER COUNTY, Colo. (CBS4)– The judge presiding over the murder trial of Patrick Frazee has said that if the defense wants to introduce an alternate suspect in the case, the deadline is Sept. 16. Frazee has been charged with murder in the death of his fiancee Kelsey Berreth.

Patrick Frazee in court (credit CBS)

Prosecutors claim Frazee, of Florrisant, killed Berreth, of Woodland Park. Investigators believe Frazee was aware that his fiancee disappeared on Thanksgiving day after dropping off their child.

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There is no mention in the court documents of who Frazee could point the finger at, but it might be his former girlfriend, who has admitted to a role only in the aftermath of the murder.

Kelsey Berreth, left, and Patrick Frazee, right (credit: Woodland Park Police/Teller County)

Frazee’s former girlfriend, Krystal Lee Kenney, has given prosecutors a horrific account of how she said Frazee told her he allegedly murdered the mother of his little girl.

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Krystal Lee Kenney (credit: CBS)

Kenney said Frazee told her he killed Berreth in her Woodland Park home by beating Berreth to death with a baseball bat. Prosecutors said that after Frazee allegedly killed Berreth he called his former girlfriend to help him clean up. Investigators said Kenney admitted watching Frazee burn Berreth’s remains outside his home.

(credit: CBS)

Kenney said initially Frazee asked her to kill the 29-year-old mother on three occasions, including suggesting poisoning Berreth’s coffee.

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Kenney pleaded guilty to tampering with evidence in the case but has denied any involvement in Berreth’s murder. Frazee’s lawyers are requesting a jury pool of some 300 people because of the widespread publicity of the trial.