And while it’s Russert’s first “Dateline,” this is a story producers have been working on for a decade.

Ten years ago, Dateline producer Dan Slepian started getting letters from an inmate named Jon-Adrian Velazquez. Valazquez is serving 25 years to life in Sing Sing prison for killing a retired NYPD police officer — a murder he says he did not commit.

Russert interviews Velazquez, his mother, his former girlfriend, his attorneys — now two years on the case — and a witness who picked Velazquez out of a lineup. That man, August Brown tells Russert, “I don’t know if I picked out the right person.”

The “Dateline” investigation airs Sunday, Feb. 12 at 7pmET/6pmCT.

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