Prosecutors are tearing into the testimony of a second defense expert who concluded the Colorado theater shooter was so mentally ill that he couldn't tell right from wrong when killed 12 people and injured 70 during a packed midnight movie premiere.

Dr. Raquel Gur will return to the stand Wednesday to face more questions from District Attorney George Brauchler, who immediately launched an aggressive attack on her credibility. Gur, head of neuropsychiatry at the University of Pennsylvania medical school, examined James Holmes and determined that he suffers schizophrenia and delusions and met the legal definition of insanity at the time of the July 20, 2012, attack.

Gur is the star witness for the defense team, and her testimony is crucial to the argument that Holmes should be found not guilty by reason of insanity and committed indefinitely to the state mental hospital. But Brauchler, who is seeking the death penalty, laced into her Tuesday, questioning the accuracy of the notes she took on her meetings with Holmes and suggesting that she came to a hasty conclusion about his mental illness and sanity.

Gur interviewed Holmes for 28 hours over two years — more than any other psychiatrist — and studied the spiral notebook where he scrawled elaborate plans for the massacre. But she acknowledged to Brauchler that she wrote her report about her conclusions after the first 13 hours of interviews.

Brauchler also noted that Gur once wrote that trial witnesses can be influenced by the side that calls them to testify. Gur retorted that Brauchler was taking the statement out of context.

Another psychiatrist called by the defense, Dr. Jonathan Woodcock, testified two weeks ago that Holmes didn't know right from wrong. Prosecutors spent nearly two days tearing apart his testimony.

In Colorado, prosecutors bear the burden of proving sanity beyond a reasonable doubt, so Brauchler is trying to quash any suggestion that Holmes was insane when he opened fire on the theater.

Two court-appointed psychiatrists who studied Holmes in the months and years after the shooting found him legally sane at the time of the attack.

In two days of questioning by defense lawyer Daniel King, Gur said Holmes' thoughts about killing other people had become an uncontrollable storm in his mind in the months before the shooting.