WHYY By An ATF board displays some the types of firearms confiscated in Philadelphia. (Kimberly Paynter/WHYY) The federal government has loaned the Philadelphia Police Department a mobile forensics unit to help investigators make more arrests for gun-related crimes. Authorities say the $250,000 vehicle, paired with a trailer dedicated to test-firing crime guns, will help reduce the amount of time it takes for experts to process ballistics evidence — evidence that could prove critical to clearing one or more open shooting cases. “The faster we can do the work, while maintaining quality, the more actionable the lead is. The longer a lead takes, the less value it may have because the time to go back and look for video, look for other things, may get lost,” said Michael Garvey, director of the city’s Office of Forensic Science.