NEW YORK (CBSNewYork/AP) — Three term Manhattan District Attorney Cy Vance, Jr. is not running for reelection.

This opens the office to a newcomer, and the race to succeed him is already packed.

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As CBS2’s Dick Brennan reports, is only one of four DAs to serve in the office in nearly 80 years – the other names are Thomas Dewey, Frank Hogan and Robert Morgenthau.

Vance leaves as his office is investigating former President Donald Trump.

Vance has decided that three terms as Manhattan DA is enough.

“I never imagined myself as District Attorney for decades like my predecessors. I never thought of this as my last job, even though it’s the best job and biggest honor I’ll ever have. I said twelve years ago that change is fundamentally good and necessary for any institution,” Vance, 66, said in a written statement.

His decision to walk away from the job was widely expected. He’s been serving since 2010.

“He focused the resources of the office on crime prevention in a way that really hadn’t been office’s mantra previously,” said Daniel Alonso, who was chief assistant district attorney in the Manhattan DA’s office during Vance’s first term.

“He wanted to use every tool in the toolbox to fight crime on the street,” Alonso said.

But Vance will be leaving right in the middle of perhaps what would be his most high profile case: A potential criminal prosecution of former President Trump concerning his businesses. He recently got the tax returns of Mr. Trump after the former president had fought turning them over.

“The investigation is a very serious one, a very complex one. It requires complexities and nuances, and look at this matter professionally and not politically,” Alonso said.

Vance successfully prosecuted Harvey Weinstein last year, but critics say he had the chance to do it much sooner – in 2015 – and didn’t. He was also criticized over the failed case against Dominique Straus Kahn, the former head of the International Monetary Fund, who was accused of sexual assault.

The office will now get a new chief, and political experts expect perhaps a leftward shift.

“It’s quite logical that the office to the left,” said Democratic strategist Hank Sheinkopf. “It seems to be the cry at the moment.”

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Eight lesser known candidates are vying in the June Democratic primary, and it’s not clear now who the front runner would be.

“There are hundreds of candidates for all kinds of offices, from mayor all the way down to city council. It’s likely in the DA’s race that somebody will break through, but it’s going to be a while away,” Sheinkopf said.

The candidates will likely promise to be tough on Mr. Trump, who got just 14% of the Manhattan vote on Nov. 3.

The winner of the primary is virtually assured to hold the office. It has been held by a Democrat since 1942.

Vance’s term expires at the end of the year.

As DA, Vance ended most prosecutions for possessing and smoking marijuana and for jumping subway turnstiles, slashing the cases handled by his office by nearly 60%, to about 42,000 in 2019. He also embraced diversionary programs for first-time offenders and established a unit to review old cases and remedy wrongful convictions.

The Supreme Court ruling on access to Trump’s taxes was a capstone for Vance’s tenure as district attorney, ending an 18-month fight with Trump’s lawyers and bolstering a grand jury investigation that has drawn worldwide attention.

Vance’s wide-ranging investigation includes examining whether Trump or his businesses lied about the value of assets to gain favorable loan terms and tax benefits, and hush-money payments paid to women on Trump’s behalf.

Vance will lead that probe through the end of this year with his general counsel, Carey Dunne, who made appeals court arguments on the office’s behalf. He recently hired former mafia prosecutor Mark Pomerantz to assist in the probe.

The Trump case will likely be an early test for the next DA. In the short term, legal observers say, Vance’s announcement could hasten the departure of prosecutors who’ve been loyal to him and won’t want to work for his successor.

The candidates have avoided speaking directly about the Trump matter, saying they didn’t want to prejudge an ongoing investigation.

Vance’s successor will be just the fourth elected district attorney in Manhattan in the last 80 years. Frank Hogan served for 31 years. Robert Morgenthau was in office for 34 years, until he was 90.

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CBSNewYork Team