Ask Greta

By Greta Van Susteren; Melissa August, Amanda Bower, Beau Briese, Rhett Butler, Kathryn Hoffman, Sora Song, Heather Won Tesoriero, Kadesha Thomas, Josh Tyrangiel

Q. Can Andrea Yates, the Houston mother who allegedly killed her kids, successfully use postpartum depression as the basis for an insanity defense?

A. To be judged legally insane in Texas, it's not enough to be depressed. You can be very blue but know you're not supposed to kill someone. Texas law says you're insane if you have a mental disease or defect--and you didn't know your conduct was wrong at the time. There's no scientific test. The jury has the almost impossible task of jumping into the accused's mind at the time of the offense.

Greta Van Susteren is host of CNN's The Point