Nassau County hires attorney Robert Costello, 'contemptuous' defense witness from Trump trial

Robert Costello, a former legal adviser to ex-Donald Trump fixer Michael Cohen, is working for the Nassau County Attorney’s Office after leaving his Manhattan law firm following his May testimony as a defense witness in the former president’s hush money trial.

Costello, 76, of Manhasset, is a former federal prosecutor who became a defense lawyer with a client list that recently included former New York City Mayor Rudy Giuliani.

Chris Boyle, a spokesman for Nassau County Executive Bruce Blakeman, confirmed Costello's hiring in response to a Newsday inquiry but declined to provide details about his hire date, job title or salary.

Boyle released a statement from Nassau County Attorney Thomas Adams that called Costello "an experienced and very accomplished lawyer and litigator."

It added that Blakeman "has made it a priority to upgrade the County Attorney's office and make it into a law firm with the most capable and competent legal minds to protect the taxpayers of Nassau County."

Costello didn't respond to messages seeking comment about his hire.

The attorney gained notoriety when he rankled Judge Juan Merchan while testifying in State Supreme Court in Manhattan on Trump's behalf.

The jury convicted Trump on 34 felony counts of falsifying business records to conceal a sexual encounter with adult film actress Stormy Daniels from the voting public ahead of the 2016 presidential election. Last week, Merchan delayed the sentencing until Nov. 26, three weeks after Trump and Vice President Kamala Harris face each other in the presidential election.

During the trial, Costello muttered "ridiculous" after Merchan sustained one objection and "jeez" after another. Costello also rolled his eyes and gave Merchan what the judge described as "side eye" while on the witness stand, Newsday previously reported.

Merchan ordered the jury out of the room and said he wanted "to discuss proper decorum in my courtroom."

The judge then cleared the courtroom after asking Costello if he was staring him down.

"I'm putting you on notice that your conduct is contemptuous," Merchan told him. "If you try to stare me down one more time, I will remove you from the stand."

Trump’s team put Costello on the witness stand to try to undermine Cohen's credibility.

Prosecutors had submitted emails into evidence they said showed Costello urging Cohen, who testified he set up the hush money arrangement, not to cooperate with a federal investigation into campaign finance law violations related to the Daniels payment.

Costello denied in his testimony that he tried to intimidate Cohen.

"I can’t imagine what favor might have been owed by Bruce Blakeman, to offer employment to Bob Costello, a lawyer who has demonstrated no respect for the law or the legal process," Cohen told Newsday in a statement.

Costello has nearly four decades of legal experience, records show. He worked for six years in the Southern District U.S. Attorney's Office before spending three decades in several Manhattan-based law firms.

Shortly after his testimony in Trump's trial, Costello left his position as a partner at Davidoff Hutcher & Citron, a law firm where he'd worked since 2017.

Law firm spokesman Zack Fink said Costello departed a few months ago.

"We greatly value his contributions to the firm over many years. And we wish him luck in all his future endeavors," he added.

In recent years, Costello garnered headlines for representing clients with deep connections to Trump.

Besides Giuliani, Costello also served as counsel to former Trump adviser Steve Bannon, who now is serving a 4-month sentence in federal prison after defying a congressional subpoena related to the Jan. 6 attack on the U.S. Capitol. In the past, Costello also has represented late New York Yankees owner George Steinbrenner and late real estate mogul Leona Helmsley. 

Nassau County Republican Chairman Joseph Cairo declined to comment Thursday about Costello's hiring.

Democrats in Nassau were critical of Costello's hire, suggesting Blakeman could be trying to curry favor with Trump as he seeks a return to the White House.

"Why should the Nassau County taxpayers foot the bill for a favor that Bruce Blakeman is doing for Trump?" said Jay Jacobs, the Democratic Party's state and Nassau chair. "You got to wonder what is in this deal."

Veteran Democratic strategist Hank Sheinkopf described the hiring as a Blakeman power play.

"Trump and Trumpism likely will remain potent in suburban locales. Blakeman knows it ... And if the former president earns another White House term, Blakeman will have a front door key," he said.

But Michael Dawidziak, a political consultant who works mostly with Republicans, said while Blakeman is clearly a "big Trump supporter," the idea that hiring Costello would influence the former president "seems like a stretch."

He added: "Giving an attorney a job wouldn't, in the grand scheme of things, raise many eyebrows."