Menachem Lieberman was 13 years old when he was coerced to be a false witness in a Rabbis' murder

He helped send a wrongly accused man to prison because of what cops told him to say — and he helped get him out because of what the Torah commanded him to do.

Menachem Lieberman was just a scared 13-year-old when police steered him to finger David Ranta for the 1990 murder of Hasidic Rabbi Chaskel Werzberger after a botched jewel heist in Williamsburg.

Ranta was released last week after nearly 23 years in prison, following a yearlong probe that determined the original cops on the case performed a shoddy investigation, failed to keep adequate notes and coached witnesses.

Lieberman was one of those witnesses 23 years ago — and his decision to finally recant his testimony was the big break in proving Ranta had been railroaded.

“A lot of things made me think back and realize that it was wrong — that a human being is in jail who should not be,” Lieberman told The Post.

It was Feb. 8, 1990, when blood was shed on Clymer Street in a robbery gone bad.

Jewel courier Chaim Weinberger — holding a suitcase filled with 50 pounds of uncut jewels worth $250,000 — was leaving his home on his way to catch a flight when he noticed he was being followed by a man with a pistol. He raced to his car and sped away, knocking the gunman down as he tore off.

The killer turned on Werzberger, who happened to be warming up his 1985 Olds that cold morning. He shot him in the head, then drove off in his car. The rabbi died four days later.

Lieberman, now 36, was on his way to a Satmar yeshiva on Heyward Street when he noticed two men sitting in a station wagon. It was strange, he thought, because the car’s ignition was off, and “they were watching the street.”

The boy went to school and later heard that someone had been shot. He called his mother from a pay phone, and when he came home — he lived in the same building as the slain rabbi — the police were waiting for him.

“They showed me binders of faces of people to try to identify, but I didn’t find anyone there,” he recalled. “I gave them a description — I don’t remember what it was now, but it didn’t match up to David Ranta.”

He met with sketch artists, looked through more mug shots, but still nothing. Weeks turned into months.

That summer, he was summoned from summer camp in upstate Napanoch by cops. Ranta, a petty crook who admitted to being near the scene, had been arrested. Detectives wanted Lieberman to view a lineup at the 90th Precinct station house.

“As I walked in, there were a couple of police officers. I don’t remember their rank, their faces. I just know that somebody said to me, ‘Pick the guy with the big nose,’ ” he said. “And if you saw [Ranta’s] face, he has a very distinct nose. You can’t mistake it, even to this day.