NEW YORK, Sept 27 (Reuters) - A New York law firm was "extraordinarily vindictive" for cutting loose a first-year associate who sent an email boasting of his "superior legal mind," according to a brief the former associate filed in his $77 million lawsuit against the firm, Kasowitz Benson Torres & Friedman.

The description "fits perfectly the conduct of the firm" toward "an enthusiastic and bright-eyed first year perhaps overly excited to get started in the practice of the law," wrote Gregory Berry in a brief filed Monday in state Supreme Court in Manhattan opposing the firm's motion to dismiss his suit.

In August, Berry sued Kasowitz Benson and two of the firm's partners, Aaron Marks and Kim Conroy, for behaving unethically, inflicting emotional distress and attempting to thwart his future career prospects. He said he was fired in May, days after he emailed the firm's partners to seek more responsibility.

"It has become clear that I have as much experience and ability as an associate many years my senior, as much skill writing and a superior legal mind to most I have met," his email said, according to his complaint.

He was informed by a partner at the firm that his email had "burned bridges" in the office, and he was fired a few days later, according to the lawsuit.

The response to his request to take on more work was "outrageous and extreme" compared to other law firms, Berry said in the brief, arguing that he should be awarded millions for the emotion distress he experienced.

"The context of the legal profession ... perhaps more than any other, is one of civility and decorum," Berry wrote. "In this context, the aggressiveness and the overt hostility, vindictiveness and pettiness to which defendants subjected plaintiff were shocking."

Kasowitz has denied Berry's claims and said that Berry is in "flagrant breach" of a confidential severance agreement that gave him $27,000 in exchange for his waiver of claims against the firm.

An attorney for the firm, Joseph Piesco, declined to comment on the brief. Berry, who is representing himself, also declined further comment.

The case is Berry v. Kasowitz Benson Torres & Friedman LLP et al, in the Supreme Court of New York, County of New York: Commercial Division, index no. 652274/2011.

For Berry: Pro se.

For Kasowitz: Joseph Piesco of Kasowitz Benson Torres & Friedman.

(Reporting by Jessica Dye)

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