Brian Mahanna, chief of staff and deputy attorney general in the Office of the New York Attorney General/courtesy photo

Brian Mahanna, the current chief of staff and deputy attorney general to New York Attorney General Barbara Underwood, said he plans to leave the public sector and join Wilmer Cutler Pickering Hale and Dorr as a partner in its New York City office in February.

Mahanna, who also once served as senior adviser to former New York City Mayor Michael Bloomberg, will be a member of the firm's Regulatory and Government Affairs Department, where he will help clients manage high-profile crises and other challenges involving regulators.

Mahanna said in an interview with the New York Law Journal that he's planning to take his experience as an executive in the state's chief law enforcement office and apply it to his work at Wilmer.

“It's going to be helping clients navigate state and local regulators, some investigations by state attorneys general, and the sort of crises that require a nimble response,” Mahanna said. “In particular, when a company comes under scrutiny not just from law enforcement, but also from legislators, the press, and the public, which is the core of what a crisis management group does.”

It's not unusual for leadership in the attorney general's office to experience turnover when a new official is elected to the office. Mahanna's successor under Attorney General-elect Letitia James will be Ibrahim Khan, her deputy as New York City public advocate. Khan is not an attorney.

Mahanna, in contrast, has experience as a litigator in both the private and public spheres. He started his legal career in New York after working for Bloomberg as an associate at Zuckerman Spaeder, a largely corporate law firm on Madison Avenue in Manhattan. He stayed there for about four years before joining the attorney general's office in 2016.

Mahanna was first hired as the deputy chief of staff in the attorney general's office that year. He was quickly elevated to his current position of chief of staff when Micah Lasher, his predecessor, left to run for state Senate that same year. Lasher is also a former Bloomberg aide.

The position of chief of staff is not limited to managing the day-to-day operations of the state attorney general's office. For the past two years, Mahanna has been a close adviser to the state attorney general, first to former Attorney General Eric Schneiderman and now to current Attorney General Barbara Underwood.

“The position here as chief of staff has provided me with a pretty broad perspective on what an attorney general's office does and the power of state law enforcement officers,” Mahanna said. “Given the breadth of the work of the AG's office, I've dealt with regulatory, criminal, and civil matters; affirmative and defensive; trial court and appellate.”

Mahanna has been responsible for overseeing all of the state's major cases and investigations for more than two years, many of which have made headlines. That includes the state's case against the Trump Foundation over its alleged participation in President Donald Trump's campaign events and a series of allegedly self-dealing transactions.

That case is arguably the most high-profile among the office's current litigation, but there are plenty of other big lawsuits in its caseload. Most recently, the office announced a lawsuit against Exxon Mobil for possibly misleading investors and earlier this year it sued former film mogul Harvey Weinstein over sexual harassment allegations at his company.

Mahanna also manages the executive division of the attorney general's office, which governs its interactions with the governor's office, the Legislature, state agencies, and attorneys general from other states. He also oversees the office's communications team.

“My job is basically to see around the corner and understand how all those pieces — litigation, media, public pressure — how they fit together and develop the office's strategy,” Mahanna said.

Mahanna's expertise will come in handy for several clients at Wilmer who have faced litigation from the attorney general's office in recent years. The firm represents Deutsche Bank, for example, which settled with the attorney general's office over misleading investors in 2016. It also represents Credit Suisse, which settled with the office in September over fraudulent electronic trading practices.

Mahanna's experience overseeing the litigation and regulatory challenges in cases such as those is expected to translate well with the clients Wilmer typically attracts.

“I think Wilmer is a go-to firm if you have really complex, regulatory matters you need to resolve. It has a long history of recruiting attorneys with government experience because they see the value those experiences bring to that firm's clients,” Mahanna said. “That part of the firm was very attractive to me — both the ability to bring people on from the government and the types of matters that would be of interest to someone like me who's bounced back and forth from government and the private sector.”

Before his career in law, Mahanna worked for Bloomberg in a variety of capacities. He started as chief of staff to Bloomberg's senior adviser in 2004. He left the office for a short time in 2005 to work on Bloomberg's re-election campaign, where he handled policy matters and communications.

That experience paid off when he was hired as director of communications for Partnership for New York City, a nonprofit business organization in the metropolitan area. His time there was short-lived. Mahanna started in 2006 at Yale Law School, where he graduated in 2009.

With a law degree in hand, Mahanna went back to work for Bloomberg for another three years until he joined the team at Zuckerman Spaeder. He helped develop Bloomberg's policy agenda during his 2009 campaign for mayor.

Mahanna then served as special assistant to Bloomberg and also as counsel to the deputy mayor for operations when Bloomberg started his third term in 2010. Then after serving as chief of staff to the senior adviser less than a decade earlier, Mahanna became senior adviser to Bloomberg in 2011.

“Working for Mike Bloomberg was really a privilege. He is a great public servant and someone who empowered everyone on his staff,” Mahanna said. “And if you kept delivering results for the city, he kept promoting you, and I was one of those people.”

Mahanna's penchant for progress has similarly impressed Underwood, who praised his tenure at the office in a statement.

“Brian is a trusted advisor and counselor, who has been integral to our office's success,” Underwood said. “He has brought a rare combination of legal savvy, strategic thinking, and sound judgment to our most difficult and important matters. WilmerHale is lucky to have Brian and his extraordinary skills and experience.”

Robert Novick, co-managing partner at Wilmer, also counts the firm as lucky for recruiting Mahanna when they did. He praised Mahanna's experience in government in a statement.

“Brian's unique combination of talent and experience will prove tremendously helpful to many of our clients,” Novick said. “We are thrilled Brian is joining us at WilmerHale and that he chose our firm as the best platform for his extraordinary abilities.”

Mahanna will leave the attorney general's office at the end of the year before joining Wilmer in February 2019.

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