TWIN FALLS, Idaho (AP) — A woman was unfairly convicted of killing her parents in 2003 because police investigators failed to consider other suspects and a previous defense attorney who was unprepared, her attorney says.

Hailey attorney Christopher Simms made the argument Tuesday in 5th District Court during a hearing to determine whether Sarah Johnson should get a new trial.

Johnson was convicted in 2005 of pulling the trigger on a .264-caliber rifle, first killing her mother as she lay in bed in the early morning hours, then turning the weapon on her father as he exited the shower in their Bellevue home. Prosecutors said Johnson killed her parents on Sept. 3, 2003, after fighting with them over her boyfriend, Bruno Santos, a 19-year-old undocumented Mexican immigrant who was living in the region.

Johnson, who is now 23, was sentenced to two life terms for the murders, plus 15 years for using a rifle. Her sentence does not have the possibility of parole.

Simms, appointed as Johnson's attorney in 2008, argued Tuesday that new fingerprint evidence on the murder weapon suggests Johnson wasn't the killer.

He also said Johnson's attorney at her trial, Bob Pangburn, wasn't prepared, and failed to act on important information. Simms also noted Pangburn's suspensions from practicing law in Oregon and Idaho.

"There is no question that on Sept. 2, 2003, there was a terrible tragedy that happened in Blaine County," Simms said. "But another person has had her life taken away from her, and she's sitting right here, a shadow of what she used to be. I submit to this court that there were two tragedies in this case and the second was the most terrible. This was a failure of the system."

Pangburn defended his work during testimony Tuesday.

"I've thought about this case many, many times, and I thought we did a good job defending her given what we had to work with," Pangburn said.

Simms said investigators didn't adequately investigate other suspects, including Santos, who is currently jailed in Blaine County on three felony drug charges. Santos, now 26, is expected to testify at the hearing.

"They simply thought they had the answer and they never deviated from that," Simms said.

The hearing is scheduled to go through Friday.