IF YOU see a SEPTA Transit Police officer in the next few days, be sure to smile - you may be on camera.

This week, the force is beginning a trial run of body-mounted cameras on its officers, an initiative officials have had their eyes on for months.

"It improves public trust," SEPTA Transit Police Chief Thomas Nestel said. "If people know police have cameras on uniform, they have more faith that officers are acting properly."

Nestel's a self-admitted fan of technology - he boasts more than 2,000 Twitter followers - and says the cameras can be a valuable tool for the force.

"Having video evidence can help us reduce complaints, help us reduce use-of-force incidents and reduce court overtime," he said.

This week's trial will include three patrol officers on the Broad Street subway and Market-Frankford El, who will test models made by VidMic, a leading manufacturer of body cameras for law-enforcement agencies.

Nestel estimates the cameras will cost between $500 and $1,500 each. If the trials are successful, he said, he'll pursue grant funding and seek to outfit all 275 officers on the force.

In addition to the cost hurdle, Nestel has concerns about the extra man hours the cameras will generate: Staff will have to log hours of footage and keep it stored properly, ensuring no video gets released without administrative clearance.

"We know other departments have had success with this," Nestel said.

"Now we're trying to see if this is conducive for the subway arena."

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