By Tony Hanson

PHILADELPHIA (CBS) — One of Philadelphia’s most successful, respected and aggressive prosecutors is now on the hunt for the innocent.

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DA Seth Williams  announced this week the formation of a new unit, the Conviction Relief Unit, and it will be led by veteran homicide prosecutor Mark Gilson.

Williams says formation of the unit is the “right thing to do” and veteran prosecutor Gilson is the perfect person for the job.

Most serious convictions are appealed, but this isn’t about technical legal issues this is about the rare case actual innocence.

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Williams says, “Where we determine that defendants are actually innocent, we must of course take corrective action. And where we determine a conviction is proper and point out the unsavory or unethical claims by the defense in making the claims of innocence.”

Gilson, an aggressive prosecutor with an overwhelming conviction rate, says this new assignment is an extension of what he has always done.

He’s not in the business of prosecuting innocent people everybody just wants to get it right.

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