Special investigators are in Philadelphia conducting a study on officer-involved shootings.
Just this week, there were three police-involved shootings in a 24-hour span.
That includes a deadly shoot-out between officers, FBI agents and two murder suspects in East Mount Airy yesterday. One of the suspects was killed.
Officer involved shootings are up from 35 in 2011, to 52 in 2012.
The study will last a year.