Say what you will about light rail, that it functions very effectively in bringing together diverse elements of the community is indisputable. By building fixed-rail lines while simultaneously cancelling bus service in areas served by the lines, transit agencies are able to assemble a high-density, target-rich environment for the thugs who gravitate to the lines. Seattlites are now finding out why the lines are referred to as "crime lines" in so many of the urban areas in which they've been built.
Here in Portland, we've become very familiar with the concept. At last count, The Oregonian newspaper had 2150 articles relating to crime along light rail lines; much of which is concentrated within three blocks of a line. But hey, the trains are "green" - well, except for the blood.