David G. Trager, Judge in Crown Heights Case, Dies at 73

David G. Trager, a federal judge in Brooklyn whose rulings were pivotal in a racially charged case in Crown Heights and in the first civil suit to challenge the Bush administration’s practice of sending terrorism suspects to countries that employ torture, died on Wednesday at his home in Brooklyn. He was 73.

The cause was pancreatic cancer, his wife, Roberta E. Weisbrod, said.

After three decades as a lawyer, state investigation commissioner, federal prosecutor and law school professor and dean, Mr. Trager was named to the United States District Court for the Eastern District by President Bill Clinton in 1993. After assuming senior status in 2006, Judge Trager worked full time until recently. The district encompasses Brooklyn, Queens, Staten Island and Nassau and Suffolk Counties.

In a wide-ranging career, Judge Trager, a Republican known for political independence, was United States attorney for the Eastern District from 1974 to 1978. He was also a professor at Brooklyn Law School for 17 years and, for a decade, its dean. From 1983 to 1990, he headed the State Commission of Investigation, and in the 1980s he advised New York mayors on judicial appointments and helped to revise the City Charter.

But he was perhaps best known as the judge in the trial of two black men, Lemrick Nelson Jr. and Charles Price, who were convicted in 1997 of civil rights violations for their roles in the killing of a Hasidic scholar, Yankel Rosenbaum, in 1991 on a night of mob violence in Crown Heights, Brooklyn.

The verdict appeared to close a wrenching case that had exemplified troubled race relations in New York. But an appeals court overturned it in 2002, saying that Judge Trager, in trying to seat a racially and religiously balanced jury, had improperly manipulated the panel’s composition. The court said he had erred in a well-intended desire to be fair and to avoid a polarizing verdict, violating constitutional trial guarantees. Mr. Nelson was retried and again convicted; Mr. Price entered a guilty plea.

Another ruling by Judge Trager figured prominently in a civil suit against the government by the Center for Constitutional Rights and Maher Arar, a Syrian-born Canadian citizen who was suspected of being a Qaeda terrorist and was detained at Kennedy International Airport in 2002 on his way home from a vacation.

Mr. Arar was held in solitary confinement in Brooklyn, interrogated without access to legal counsel and, under the Bush administration’s practice of “extraordinary rendition,” sent without charges or a trial to Syria, where he was imprisoned for 10 months in a rat-infested dungeon and tortured repeatedly. Syria found no evidence that Mr. Arar was a terrorist, and released him.

In 2006, Judge Trager dismissed Mr. Arar’s suit for damages, upholding the government’s contention that torture in rendition cases was a foreign-policy issue not appropriate for judicial review and that the case might disclose state secrets. The decision was upheld by the United States Court of Appeals for the Second Circuit, and the United States Supreme Court declined to hear the case.

David Gershon Trager was born in Mount Vernon, N.Y., on Dec. 23, 1937, the son of Sol and Clara Trager, who had emigrated from Austria. He graduated from Columbia University in 1959 and received his law degree from Harvard in 1962.

Mr. Trager practiced law in New York from 1963 to 1967, and after a year as an assistant city corporation counsel, he was a law clerk in 1968 for Judge Kenneth B. Keating and in 1969 for Chief Judge Stanley H. Fuld, both of the New York Court of Appeals.

Besides his wife, whom he married in 1972, Judge Trager is survived by a son, Josiah; two daughters, Naomi Trager and Mara Trager; and two grandchildren.

In the early 1970s, Mr. Trager was an assistant federal prosecutor in Brooklyn and an associate professor at Brooklyn Law School. He taught constitutional law at the school, where he was a full professor from 1978 to 1993 and the dean from 1983 to 1993.

As the United States attorney in Brooklyn in the mid-1970s, Mr. Trager was known for vigorously pursuing organized crime. While he had no prosecutorial powers as chairman of the State Commission of Investigation in the 1980s, he exposed numerous cases of official corruption, notably on Long Island.

In 1987, after a 14-month inquiry, he disclosed what he called a “startling lack of professionalism” in the Suffolk County Police Department, with instances of perjury, fabrication and illegal wiretapping that he said were “shamefully tolerated” by the district attorney’s office. A wave of retirements, resignations, transfers and reforms ensued.

Mr. Trager was a member of panels that advised Mayors Edward I. Koch and David N. Dinkins on judicial appointments and that revised the New York City Charter, eliminating the Board of Estimate, which had been the center of civic affairs for a century, and redistributing the board’s powers to an expanded City Council, the mayor and a reconstituted Planning Commission.