Former Rep. Edward Hutchinson, 70, a Michigan conservative who was the ranking Republican on the House Judiciary Committee when it voted 27 to 11 to impeach President Nixon, died July 22 at a hospital in Naples, Fla. The cause of death was not reported. He had homes in Naples and in Fennville, Mich.

Mr. Hutchinson voted against every article of impeachment brought against the president even after other Republicans had abandoned him. After the committee vote and further Watergate-related revelations, Mr. Hutchinson called for Nixon's resignation.

During the impeachment hearings, he was seen by many as a man who had little influence on the voices and votes of his Republican colleagues. But he succeeded in walking a fine line of party and institutional loyalty.

If he expressed a somewhat convoluted theory of constitutional law in defense of his president and party leader, he closed ranks with committee chairman Peter Rodino (D-N.J.) in institutional confrontations with the White House.

Early on in the proceedings, he and Rodino reached agreements on the role of the Republican minority on the committee, which included the appointment by Mr. Hutchinson of a third of the special staff. While continuing to support the president, he defended that staff against attacks by other minority members who claimed that they were too close to the Democrats.

Mr. Hutchinson was elected to the House in 1962 and served until 1977, when he retired. He was proud of his election to the House Standards of Official Conduct, or Ethics, Committee. Liberal Democrats called him a "decent conservative."

Born in Fennville in southwest Michigan, he served his region for much of his life. After graduating from the University of Michigan and its law school he served in the Army during World War II. In 1946, he won election to the Michigan House of Representatives. After four years there, he served 10 years in the state senate.

In 1960, he was defeated in a try for the Republican nomination for lieutenant governor. In 1961, he and George Romney, former Michigan governor and Nixon cabinet officer, served as vice presidents of the state constitutional convention.

In the House of Representatives, Mr. Hutchinson voted against all major civil rights legislation. By the end of his House career, he was widely considered the most conservative member of his state's congressional delegation. He was succeeded in the House by David Stockman, who recently resigned as director of the Office of Management and Budget.

Mr. Hutchinson's survivors include his wife, the former Janice Caton, whom he married in 1959, and a brother, Robert Hutchinson of Fennville.