PHILADELPHIA (CBS) - After more than a quarter of a century of locking up criminals in Bucks County, Prosecutor David Zellis is switching gears, leaving the office yesterday to pursue another opportunity that he believes can help many people in the community.

The 51-year-old Zellis (photo) has spent 26 years in the courthouse in Doylestown, his only job since leaving law school. He says he had a life-changing experience creating and implementing a drug court, seeing firsthand what substance abuse can do to an addict and a family. He’s becoming a defense attorney to work more closely to help families and individuals work toward fighting addiction.

“This is just a wonderful opportunity for me to be out in the community and you know it’s kind of like a mid-life crisis I guess for me – changing jobs and going with a lot of excitement and enthusiasm.”

He’s most proud of a yearly symposium that educates people on how to better protect seniors that was born out of a conviction of a worker at a personal care home. He gained national notoriety with the Mary Jane Fonder church shooting case. But he also leaves the DA’s office without closing the murder of attorney Eric Birnbaum who was gunned down in a Holland parking lot.

Reported by Brad Segall, KYW Newsradio