Routt County Judge Michael O'Hara denied several requests for a mistrial Thursday in the first-degree murder case of Steamboat Springs resident Luz Cisneros.
The case continued Thursday, one day after public defender Sheryl Uhlmann called for a mistrial in the wake of surprising testimony from Isaias Simon, the father of the 1-year-old Cisneros is accused of killing. On Wednesday, Simon said his relationship with Cisneros was falling apart because she was cheating on him. It previously had been reported that Simon was unfaithful to Cisneros.
The defense argued that such "bad character" testimony against Cisneros fundamentally undermined her right to a fair trial. O'Hara disagreed.
Throughout the trial, the defense has acknowledged that Cisneros killed her daughter, but it alleges the crime was committed in a moment during which she was so overwhelmed by the emotion of her failing relationship that she could not have acted with the necessary intent and deliberation to be convicted of first-degree murder.
Simon ultimately got back on the stand Thursday morning and testified that although Cisneros repeatedly threatened to kill their daughter and herself in the weeks leading up to Brianna Simon's Sept. 6, 2007, death, he never believed she was serious.
"She was a very loving mother, until that day," Simon said. "I'd never seen her like that before."
Cisneros, 34, faces life in prison without the possibility of parole if convicted.
Uhlmann also requested a mistrial when Assistant District Attorney Elizabeth Oldham held up in view of the jury an inadmissible photograph of the bloody shirt Brianna was wearing when she was killed.
A third mistrial motion was made Thursday afternoon while jurors listened to a nearly four-hour recording of Cisneros' interrogation at the Steamboat Springs Police Department on the day of her daughter's death. The defense objected to the inclusion of an inadmissible portion of the interview in the accompanying transcript provided to jurors.
O'Hara denied both additional mistrial requests.
Jurors also heard testimony Thursday from Colorado Bureau of Investigation staff who collected and processed evidence from Cisneros' apartment.
Cisneros' trial is scheduled to resume at 8:30 a.m. today in Routt County District Court. The prosecution's final witness, former Steamboat Springs police Det. Matt Harmon, will finish his testimony this morning, and the defense will begin calling its witnesses this afternoon.
The trial is scheduled to conclude Tuesday.