NEW YORK, Aug 15 (Reuters) - David Bernick, an experienced litigator and the recently departed general counsel of Philip Morris International Inc, has joined Boies, Schiller & Flexner, the law firm led by celebrated attorney David Boies.

Bernick, 58, resigned from Philip Morris in February after about two years on the job. Previously he had been a partner at the international law firm Kirkland & Ellis.

Bernick will start immediately, working at Boies Schiller's New York office.

The hire, which gives Boies Schiller another accomplished trial attorney, represents a rare high-level partner acquisition for the firm. Bernick is only the fourth senior partner the firm has brought on since it was founded 15 years ago.

"It's a huge step for the firm," said Boies, who represented former vice president Al Gore at the Supreme Court over the 2000 presidential election.

Boies and Bernick discussed Bernick's move, the direction of Boies Schiller and the state of the law firm business in an interview with Reuters in New York last week.

Bernick said his short stint at Philip Morris was a positive experience. He said he left because he missed implementing strategies for clients and also because he was anxious to get back into the courtroom.

"Once a duck learns to swim, you never forget it," he said.

Before Philip Morris, Bernick was a senior partner and a member of the management committee at Kirkland & Ellis. His litigation practice varied widely in his 31 years at the firm: He gained widespread attention for defense work for tobacco companies, breast-implant makers and corporations with asbestos liability.

In 2009, he won an acquittal for WR Grace & Co, which was accused by the U.S. Department of Justice of knowingly endangering the lives of residents in Libby, Montana, and concealing information about its asbestos mining operations.

Bernick was recruited to Boies Schiller by partner William Ohlemeyer, with whom he had worked on tobacco litigation in the 1990s. Bernick said he was struck by the speed with which Boies Schiller had built an identity that extended beyond Boies.

"You now have a new organization with its own brand," Bernick said.

At 71, Boies is still the public face of the firm. And he shows no evidence of slowing down. In the last two years, he has represented Oracle Corp in two high-profile trials and taken on the federal government in a case over the bailout of American International Group Inc on behalf of the insurer's former chief executive, Maurice "Hank" Greenberg. He has also been the lead lawyer, along with Theodore Olson, in a case challenging California's ban on gay marriage.

But Boies Schiller has expanded well beyond Boies. After starting off with eight lawyers in 1997, the law firm today has more than 250, mostly devoted to litigation and a growing corporate practice. It also is now among the top 100 U.S. law firms by gross revenue and among the top 15 measured by profits per partner, according to The American Lawyer magazine.

Boies, wearing his customary navy jacket and a plaid shirt, said that while the firm has seen its profits reduced during the financial crisis, it has not had to lay off attorneys, unlike some of its competitors. It has also not had to rescind any job offers to new recruits.

The financial crisis has actually helped the firm pick up some new clients, he said. Before 2008, the firm had not represented many financial institutions and instead marketed its ability to sue banks, which other law firms with strong ties to Wall Street were unwilling to do.

But the firm began to break that pattern as the financial crisis spawned litigation against and among the banks. Barclays Plc, for instance, hired the firm to defend against a claim that it wrongly reaped an $11 billion windfall when it bought the U.S. investment banking brokerage operations of Lehman Brothers Holdings Inc in 2008.

Since the court ruled in favor of Barclays, the bank has doled out more work to Boies Schiller, including a role as counsel in the scandal involving the alleged rigging of the interest rate known as Libor.

Bank of New York Mellon Corp has also given the firm more work in recent years and HSBC Holdings has become a client, according to Boies.

"HSBC, Barclays and Bank of New York are now three of our largest clients," he said.

When Boies started the firm, the business plan was to devote 40 percent of its time to repeat clients, with the rest devoted to one-off engagements and other types of assignments. But Boies said that around 65 percent of the firm's time is now devoted to its core clients.

It's unclear how many of the repeat clients would stay with the firm if Boies decided to, say, work full-time on his wine vineyard in California. But Boies said that the firm's upward trajectory would continue without him.

"Unlike any other firm that has grown up as a litigation specialist firm ... we have serious core clients," said Boies. "There's isn't another firm our size ... that has the kind of core clients we have."

(Reporting by Andrew Longstreth)

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