Updated

A psychiatrist testifying for prosecutors says there is no way that an antidepressant drug could have made a Missouri teenager kill a 9-year-old neighbor girl.

Dr. Anthony Rothschild testified Tuesday in the sentencing hearing for Alyssa Bustamante, who has pleaded guilty to strangling, stabbing and slicing the throat of Elizabeth Olten of St. Martin's in October 2009.

Defense attorneys who are arguing for a sentence less than the maximum of life in prison have sought to show that the antidepressant Prozac could have contributed to Bustamante's mood swings and violent tendencies.

But Rothschild says there is no scientific or medical evidence that Prozac causes people to commit murder. To the contrary, he says it actually can decrease hostility and aggression.