ON THE FRONT LINES A young victim of a hit and run is brought to the ER...A college student thinks she may have been raped....A homeless man is covered with chemical burns but won't say how he got them... Across the country, in moments of crisis, nurses are often the first witnesses to acts of trauma. And when the human body itself is a crime scene, what a nurse does--from asking the right questions to preserving the key evidence--can make all the...