Sasha Osinski is an accomplice of Alex Petrovich in a money laundering scheme that led to Petrovich killing Karl and Evelyn Jarmon. Sasha was called to testify, but only agreed to immunity for the murders.
He was arrested for only receiving immunity in New York County, not New York City, so he was set to be tried in Brooklyn for his financial crimes.
Osinski was found guilty of money laundering and imprisoned. (L&O: “The Serpent's Tooth”)