A man convicted of murder by a Bronx jury will go free because prosecutors took too long to get his case to trial, a panel of state appeals court judges ruled.

Mark McDonald, 43, waited six years to be tried in Bronx Supreme Court in the January 2011 fatal shooting of Angasha Sharras, 29, in Williamsbridge. He was finally convicted at trial in March 2017, and Justice Ethan Greenberg sentenced McDonald to 23 years to life in prison.

But McDonald’s six-year wait to be tried led a three-judge Appellate Division panel to overturn his conviction, saying that the Bronx district attorney’s office had “no good cause” to violate McDonald’s right to a speedy trial by delaying the case until 2017.

“The pretrial delay of almost six years was unreasonably long, and defendant was incarcerated throughout that time,” the judges wrote in a decision dated Tuesday.

“While the charges against defendant were very serious, this was a relatively simple case that did not warrant such an extraordinary delay in bringing defendant to trial,” the judges wrote.

Troy Smith, McDonald’s trial lawyer, said in 28 years of practicing law after 10 years as a Bronx prosecutor, he’s never seen such an outcome on a speedy trial appeal.

“I’m very pleasantly surprised for the client because it’s an incredibly difficult hurdle to overcome,” Smith said.

The DA’s office now has 30 days to file a request to appeal. “We are considering whether to appeal the decision,” said Patrice O’Shaughnessy, a spokeswoman for the district attorney’s office.

The case spans the tenures of two Bronx district attorneys. It began in 2011 under Bronx DA Robert Johnson. The current DA, Darcel Clark, took office in 2016.

Legal experts agreed the appellate panel’s decision is highly unusual. “The delay here is extraordinary — six years — and where the prosecution has failed to explain their dereliction in not trying the case sooner,” said Bennett Gershman, a law professor at Pace University.

“Delays typically work to a defendant’s benefit. But this result is really a stunning rebuke to the Bronx DA and does send a strong message.”

The appellate panel said the DA’s office switched three prosecutors onto the case and then claimed further delays because a key detective was sick and couldn’t testify. But the judges ruled that another detective could have easily given the same testimony.

“After the case was assigned to the third and final prosecutor in mid-2014, he waited about one year before seeking to obtain a DNA sample from defendant,” the judges wrote.

Law Prof. Ellen Yaroshefsky said that although McDonald was convicted by a jury, the decision raises the question of whether the long delay was a tactic to get him to plead guilty.

“It’s yet another example of the common practice by prosecutors of just delaying in the hope that they will get a plea,” said Yaroshefsky, who teaches at Hofstra University School of Law.

“This was before the new discovery law, so the DA didn’t have to turn over a good deal of information. It’s a good example of trying to force the plea.”

McDonald’s appeals lawyer Abigail Everett declined to comment.

The Sixth Amendment to the Constitution lays out criminal defendants’ right to a “speedy and public trial.” New York State law holds that the trial must take place within six months of indictment unless waived or other factors intervene.