NEW YORK (AP) — An important figure in the Martha Stewart stock-fraud trial collapsed at a train station and died, just two days after giving testimony that appeared to damage the defense.

Jeremiah Gutman, an 80-year-old lawyer who once represented the star witness for the prosecution, collapsed Wednesday on a Metro-North platform in Hastings in suburban Westchester County.

He was found unconscious on a staircase and died later at a hospital, Metro-North spokeswoman Marjorie Anders said Thursday. The cause was an apparent heart attack, associates of the lawyer said.

Gutman represented Merrill Lynch & Co. assistant Douglas Faneuil in early 2002, shortly after Faneuil handled Stewart's sale of nearly 3,928 shares of ImClone Systems stock.

Faneuil initially told investigators Stewart sold after he gave her a stock quote. But he changed his story in 2002, saying broker Peter Bacanovic had ordered him to tip Stewart that ImClone CEO Sam Waksal was trying to sell his own shares.

Gutman testified on Monday, called as a witness by Bacanovic's lawyers - but his testimony appeared to backfire on the defense as he backed up essential pieces of Faneuil's story.

Gutman testified that Faneuil was distraught to the point of tears in the early days of the ImClone investigation - months before he went to the government and claimed he had lied for Bacanovic.

Earlier in the trial, Faneuil testified that Gutman had told him he knew about a deal between Merrill Lynch and the government to ignore any wrongdoing by Stewart and hand over Waksal "on a silver platter."

The defense has claimed that story is a lie. But Gutman said on the stand that he told Faneuil "something like that."

Gutman said a Merrill official "had told me that he was working on making a deal and that deal would involve getting all Merrill Lynch people off the hook, and let the chips fall where they may."

The lawyer also said Faneuil told him his bosses at Merrill were "merciless and immoral."

Merrill has denied the existence of any deal.

Gutman was active in the civil rights movement in the South in the 1960s and devoted much of his life to protecting the First Amendment, said Joan Bertin, executive director of the National Coalition Against Censorship.

"He was committed to a full range of civil rights and racial equality and gender equality, but I think he appreciated in a way that many people don't how those issues stand on the shoulders of the right to free expression and political dissent," Bertin said