LOS ANGELES, Calif. — The murder case against Rob Reiner’s disturbed son Nick Reiner was dramatically upended Wednesday when his high priced celebrity lawer Alan Jackson dropped his client — and left him with a public defender instead.

Jackson told a judge that he had “no choice” but to withdraw as the attorney for the 32-year-old celebrity scion — but claimed he was legally prohibited from publicly explaining why.

Despite this, he declared that “Nick Reiner is not guilty of murder.”

Nick Reiner was in a Los Angeles courtroom to answer to charges he slaughtered his beloved movie director dad Rob Reiner, and his mom Michele. REUTERS

Reiner wore a brown jumpsuit with a white t-shirt underneath, shackled at his wrists and ankles, to court on Wednesday. Mona Shafer Edwards / BACKGRID

Nick Reiner appears in court facing charges that he murdered his parents in Los Angeles on Wednesday in a courtroom sketch. via REUTERS

Reiner smirked and smiled in a Los Angeles Superior court — wearing a brown jumpsuit, with a white t-shirt underneath and shackled at his wrists and ankles. The jumpsuit was a different look than Reiner’s last appearance where he wore a blue suicide smock.

He only addressed Judge Theresa McGonigle once when asked if he agreed to a next court date of Feb. 23.

“Yeah, I agree to that,” the wayward son said.

A group of Nick Reiner’s lawyers, including Jackson, were in court with him.

But Jackson — who notably recently helped Karen Read clinch an acquittal in the murder of her cop boyfriend — announced he and his firm would be withdrawing from the case.

Jackson said he was making the decision with Nick Reiner’s “understanding and consent.”

Reiner smirked in court as his lawyer quit, with a public defender taking over. Getty Images for Wynn Las Vegas

Lawyer Alan Jackson, who notable most recently helped clinch an acquittal on murder charges for Karen Read, told a judge that he had “no choice” but to withdraw from representing Reiner. David Buchan for NY Post

“We feel that we have no choice at this juncture but to withdraw as counsel and ask to be relieved, ” the defense attorney said, announcing he and his firm would be withdrawing from the case. Eric Thayer/Pool/Shutterstock

“We feel that we have no choice at this juncture but to withdraw as counsel and ask to be relieved, ” the defense attorney said.

 Jackson said public defenders “are ready for the appointment immediately forthwith.”

Jackson did not explain the reason for his withdrawal.

Kimberly Greene with the public defenders took over as Nick’s lawyer.

Attorney Alan Jackson (right), addresses the court during an arraignment for Nick Reiner in Los Angeles on Wednesday. via REUTERS

Nick Reiner is accused of slashing his parents’ throats and stabbing them in their Brentwood mansion. REUTERS

Here’s the latest on the death of Rob Reiner:

Before the hearing began, Nick Reiner spoke calmly with his team before they went into the judge’s private chambers for a roughly three-minute long secret meeting.

At one point Nick Reiner smirked before he began staring straight ahead while the defense team was out of the courtroom.

The hearing had initially been scheduled for Nick Reiner to enter a plea to two charges of first-degree murder. But that was postponed by Jackson quitting the case.

Afterwards, Jackson told a scrum of reporters, “Circumstances beyond our control, but more importantly, circumstances beyond Nick’s control, have dictated that sadly it’s made it impossible for us to continue our representation of Nick.”

The lawyer said he couldn’t “legally or ethically” say why.

At his first hearing, Nick Reiner donned a blue suicide vest in court. REUTERS

The hearing had initially been scheduled for Nick Reiner to enter a plea to two charges of first-degree murder, which was postponed presumably by Jackson quitting the case. / SplashNews.com

Still, Jackson said he and his team “remain deeply, deeply committed to Nick Reiner and to his best interests.”

“In fact, we know, we’re not just convinced, we know that the legal process will reveal the true facts of the circumstances surrounding this case, Nick’s case,” Jackson continued.

The defense attorney said after spending “literally every waking hour” and investigating the case “top to bottom,” he learned, “Nick Reiner is not guilty of murder. Print that!”

Meanwhile, LA County District Attorney Nathan Hochman in his own statement to the media said “We are fully confident that a jury will convict Nick Reiner beyond a reasonable doubt of the brutal murders of his parents.”

Nick’s sister, Romy, found her dead parents when she went to check on them. michelereiner/Instagram

At his first court appearance last month he was forced to wear a blue suicide vest but he’s since been taken off of suicide watch.

Rob, 78, and Michele Singer Reiner, 70, attended Conan O’Brien’s holiday party with Nick hours before the killings. Nick got into a blowout with his parents at the party possibly because he was back on drugs and refusing to return to rehab, sources told The Post last month.

Hours later, Nick — who’d been in rehab 17 times because of his fight with addiction — is accused of carrying out the murders and then fleeing. He was arrested a few hours later 15 minutes away from the home, which had a guesthouse on the property that Nick lived in.

Nick’s sister, Romy, found her dead parents when she went to check on them after a massage therapist was left waiting outside the Reiner gate with no response from inside, the New York Times reported.

The police were called to the home at least six times in 2013, 2014, 2017, and two times in 2019 for welfare, mental health and family violence, according to LAPD records.

The DA’s office has yet to announce whether they plan to pursue the death penalty in Nick’s case. But California Gov. Gavin Newsom in 2019 signed an executive order prohibiting capital punishment. It’s unclear if that order will remain in place when he vacates office at the end of his final term in January 2027.