Otis G. Pike, a longtime congressman from New York who spearheaded an inquiry in the 1970s into accusations that the intelligence establishment had abused its power, died on Monday in Vero Beach, Fla. He was 92.

His daughter, Lois Pike Eyre, said he had entered a hospice a week ago.

Over 18 years in the House of Representatives as a Democrat from a heavily Republican district on Long Island, Mr. Pike styled himself an uninhibited, independent thinker, lashing out, for example, against military profligacy.

In 1975, he became chairman of the House Select Committee on Intelligence, which began examining suspicions that the Central Intelligence Agency had had its hand in coups in Chile and other countries and was spying on American citizens. The inquiry paralleled one in the Senate; they were the first in which Congress looked into allegations of abuse by the C.I.A.

Mr. Pike maintained that the security agencies were inept bureaucracies that left the country vulnerable. “If an attack were to be launched on America in the very near future,” he said in late 1975, “it is my belief that America would not know that the attack was about to be launched.”