Opening statements began this week in the trial of the Colorado woman who is charged with first-degree murder in connection with the death of her stepson.

Letecia Stauch is accused of murdering 11-year-old Gannon Stauch, on Jan. 27, 2020. According to the arrest affidavit, previously obtained by PEOPLE, Stauch reported Gannon missing on Jan. 27, which is the same day investigators believe he was murdered.

“Evidence recovered from the residence and inside Gannon’s bedroom supports that a violent event occurred in the bedroom,” reads the affidavit, “which caused bloodshed, including blood spatter on the walls, and enough blood loss to stain his mattress, soak through the carpet, the carpet pad, and stain the concrete below his bed.”

According to the affidavit, Letecia asked her 17-year-old daughter to purchase trash bags, baking soda and carpet powder before calling 911 to report Gannon missing. Investigators said these items were used to clean up blood.

On March 17, 2020, Gannon’s remains were found in Florida, and Letecia was charged with first-degree murder.

Stauch has pleaded not guilty by reason of insanity, The Denver Post reports.

District Attorney Michael Allen began opening statements on Monday and claimed that Letecia stabbed Gannon 18 times, then shot him three times, The Gazette reports. Allen also said that during the trial, he would prove she was sane during the killing.

“The evidence will show she could distinguish between right and wrong,” Allen said, The Gazette reports.

When Letecia’s defense attorney Will Cook began his opening statements, he showed a photo that Letecia and Gannon allegedly took the day before the murder and as he did so, Letecia began to cry, according to The Gazette.

“Behind those photos and smiles Ms. Stauch was dealing with trauma and abuse that had been going on since she was a toddler,” Cook said, The Gazette reports.

Cook said Letecia was sexually abused as a child, which caused her to develop dissociative identity disorder, formerly known as multiple personality disorder.

“The person she was killing that day, attacking, it wasn’t Gannon,” Cook said, The Denver Post reports. “It wasn’t Gannon to her. She didn’t wake up that day and go, ‘I’m going to kill my stepson.’ No. She was killing the demons… from the dark depths of her childhood and her life.”

To counter that claim, Allen said Letecia was deliberate in committing and attempting to hide her crime.

“The defendant took very deliberate action,” he said, The Denver Post reports. “She decided to hide her crimes from the world.”

According to online court records previously obtained by PEOPLE, Gannon’s father, Eugene Albert Stauch, filed for divorce from Letecia in March 2020.

The trial is expected to last between six and eight weeks.

If you suspect child abuse, call the Childhelp National Child Abuse Hotline at 1-800-4-A-Child or 1-800-422-4453, or go to All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.