Captioning sponsored by Macneil Lehrer productions ifill a new study shows most teenagers who think about, or attempt, suicide have already had some Mental Health treatment. Good evening, im gwen ifill. Brown and im jeffrey brown. On the newshour tonight, we get the latest on the findings coming in the largest study ever of suicidal behavior among adolescents. Ifill then, we turn to todays arguments at the Supreme Court over whether police need waants to order blood tests for suspected drunk drivers. Brown should the number of u. S. Troops in afghanistan fall to zero by the end of next year . Judy woodruff gets two views of that option one the Obama Administration says it may consider. Ifill ray suarez has the story of playful robots given a very Serious Mission helping people with special needs from elderly adults to autistic children. This kind of a tool might be an interesting way to bridge the gap, pull the child, if you will, from the world of objects and the focus on objects over