A disgraced Brooklyn narcotics cop was sentenced yesterday to five years’ probation for a conspiracy to steal drugs from suspects and give the dope to snitches.

Sean Johnstone, who was fired from the NYPD after his felony conspiracy conviction in January, deserved to be sent to jail because he “abused his position” and tainted 200 drug prosecutions, Assistant District Attorney Charles Guria told Brooklyn Supreme Court Justice John Walsh.

But Walsh, a former cop, rejected prison for Johnstone, saying removal from society and rehabilitation were not issues for Johnstone and jailing him would not prevent more corruption.

“I have yet to see a jail sentence deter a public official from misconduct,” Walsh said.

Outside court, Johnstone’s lawyer, Anthony Ricco, said Walsh “did the right thing.”