BANGOR — The six-day, jury-waived trial of a 25-year-old mother charged with murder in the death of her nearly 2½-year-old daughter last year ended Thursday with closing arguments at the Penobscot Judicial Center.

Leanna Norris, 25, of Auburn, formerly of Stetson, did not take the stand in her own defense. She is charged with intentional or knowing murder in the death of Loh Melody Grenda. Norris has pleaded not guilty by reason of insanity but has not denied killing her child.

Superior Court Justice Ann Murray on Thursday took the case under advisement. The judge did not indicate when she would issue her decision.

Norris repeatedly admitted to investigators that on the evening of June 23, 2013, she gave her daughter three times the normal dose of an antihistamine, put duct tape over her mouth and nose, then smothered her with a blanket over her face so she would not have to watch her die, according to trial testimony.

The mother then took the rest of the antihistamine and swallowed 200 Advil pills in a botched suicide attempt.

To be found not criminally responsible for the death of Loh Melody Grenda, the defense must prove by a preponderance of the evidence that Norris suffered from an abnormal condition of the mind and lacked the substantial capacity to understand or appreciate the wrongfulness of her conduct when she smothered the girl.

Ann LeBlanc, director of the state forensic service, testified Thursday for the prosecution that Norris was suffering from major depression and an anxiety disorder when she killed her daughter. She was not psychotic or delusional when the child died, LeBlanc said.

Assistant Attorney General Leane Zainea told Murray in her closing argument that Norris was sane when she killed the girl. The prosecutor said that Norris’ actions leading up to the killing “were not impulsive but were calculating.”

“Why, if she didn’t know it was wrong to kill her daughter, did she cover her with a blanket?” Zaniea said. “She wanted to distance herself from the the crime. She didn’t want to look so coldhearted to the people who found them. Why care what other people thought if she didn’t know that what she was doing was wrong?”

Defense attorney Martha Harris of Bangor said that Norris’ actions were a result of a mental disease or defect.

“She thought she was doing the right thing, the only thing that was possible for her daughter and herself. Her reasoning process was extremely narrow and rigid. She could not see the world as it actually was.”

The toddler’s father, Michael Grenda, 27, of Auburnwas in the court for closing arguments. He testified the first day of the trial. Norris’ parents, who testified during the week of Oct. 27, were not in court Thursday.

If convicted of murder, Norris faces between 25 years and life in prison. She would be committed to Riverview Psychiatric Hospital in Augusta if Murray finds her not guilty by reason of insanity.

Norris has been held without bail at the Penobscot County Jail since her arrest July 3, 2013, when she was released from a psychiatric ward at a Rockport hospital.

To reach a suicide prevention hot line, call 888-568-1112 or 800-273-TALK (8255), or visit www.suicidepreventionlifeline.org.