A Brooklyn man, released after 19 years behind bars on a wrongful murder rap, walked free Thursday with his grandmother on his arm.

“I waited a long time for this day to happen,” said Sheldon Thomas at the Brooklyn court hearing where his name was finally cleared and his freedom finally restored. “There were so many times, when I was in my cell, that I thought of this moment.”

The 35-year-old was exonerated after an investigation by the Brooklyn District Attorney’s Conviction Review Unit determined his conviction for the fatal Christmas Eve 2004 shooting of a 14-year-old boy was rife with errors, said District Attorney Eric Gonzalez.

The prosecution was based on a sketchy photo array identification where none of the pictures showed were Thomas, with an NYPD detective later admitting that he falsely testified Thomas was in the array shown to a witness.

Investigators actually presented witnesses with a photo of a different man with the same name.

Thomas, who planned to enjoy a meal of oxtail on the first day outside jail since his arrest, recalled how his sentencing judge described him as “a menace to society” who deserved the imposed sentence of 25 years to life for murder.

“He was wrong,” said Thomas. “I didn’t deserve what happened. And I forgive him.”

Teen victim Anderson Bercy was killed and a second person wounded in the East Flatbush shooting where Thomas was quickly targeted by police and eventually convicted by their misconduct.

“An extensive re-investigation by my Conviction Review Unit revealed [the probe] was compromised from the start by grave errors and the lack of probable cause to arrest Mr. Thomas,” said Gonzalez.

The identification of a different person with the same name was first concealed and then explained away during the proceedings, he added.

Thomas was one of three alleged gang members arrested for the killing. The shooters fled the scene in a white car, with a witness identifying the other two men but not Thomas, authorities said.

Yet police “went to the defendant’s house, kicked in his front door and arrested him without a warrant, violating his Fourth Amendment rights” said Charles Linehan of the CRU. He added a detective in the case targeted Thomas “because his gut told him that he had the right person.”

According to the district attorney, Thomas was arrested despite the bad identification and his claims of innocence. A detective in the case said an anonymous tip led investigators to Thomas, adding he actually told police the “Sheldon Thomas” photo shown to witnesses was a different man.

But a Brooklyn judge nevertheless ruled there was probable cause to arrest Thomas based on information from the “unknown callers” and his resemblance to the other Sheldon Thomas, according to Gonzalez.

One of the officers involved in the case was later disciplined by the police Internal Affairs Bureau. Charges were dropped against one co-defendant before a second suspect who allegedly threatened the victims two days before the shooting was acquitted at trial.

The new investigation found Thomas “was denied due process at every stage, making his conviction fundamentally unfair.” The CRU decision declared the case cannot be retried and called for the dismissal of the underlying indictment.

The dismissal was the 34th conviction vacated following re-investigations by the unit, although the victim’s aunt questioned the decision by prosecutors.

“That’s so unfortunate,” Edelyne Bercy, 58, told the Daily News. “That’s really unfortunate ... The mother and father handled the court. I don’t know. Justice has to be done somehow.”

She recalled her nephew, shot one block from home, died on the steps outside his residence. The victim was born in Haiti and immigrated to New York with his family to find a better life.

“We come for opportunities, to get education,” said the aunt. “I was so shocked when he died. It’s something I will never, never forget.”

But Gonzalez made it clear the case against Thomas was deeply flawed and put the wrong man behind bars from its start until Thursday’s release.

“He never once wavered on his innocence all these years,” said Gonzalez. “Today I wished him good luck with the rest of his life. We can never give him back what was taken from him.”