I’ve posted repeatedly that DUI roadblocks, aka "sobriety checkpoints", are ineffective at apprehending drunk drivers.  See, for example, Do DUI Roadblocks Work? and Do DUI Roadblocks Work? (part 2).  Faced with irrefutable facts, police agencies simply switch horses and say that they are effective as deterrents.  In other words, "Ok, they don’t work but they scare [...]

Read the complete post at http://www.duiblog.com/2009/12/18/dui-roadblocks-act-as-deterrents-but-dont-tell-anyone/