The House voted 322 to 87 last night to renew the independent counsel law after beating down a Republican attempt to subject members of Congress to its special investigations.

The bill, which the Justice Department has assailed as unconstitutional, would extend for five years the system providing for court-appointed prosecutors to investigate alleged crimes on the part of high-ranking administration officials. New provisions would strengthen the system against recent restrictions devised by the Justice Department under Attorney General Edwin Meese III.

The current law will expire in January unless Congress reauthorizes it. A similar bill is awaiting floor action in the Senate.

GOP opponents, led by Rep. E. Clay Shaw (Fla.), charged in a day-long debate that costs of the investigations, especially the Iran-contra inquiry by independent counsel Lawrence E. Walsh, were exorbitant; that there has yet to be a conviction of any "covered" official under the 10-year-old system, and that the House was displaying its hypocrisy by refusing to bring itself under the law.

"The system of ethics we have around here is a farce," said Rep. Henry J. Hyde (R-Ill.). "It can't be said that we do a good job of investigating ourselves."

The move to bring members of the House and Senate under mandatory coverage of the law was rejected on a predominantly party-line vote of 243 to 169. Democrats denounced the proposal as a thinly disguised attempt to kill the bill. They said the attorney general would still be free under a "catchall" clause to seek appointment of independent counsels for anyone, including lawmakers, when investigation by the Justice Department would pose "a personal, financial or political conflict of interest."

House Democrats, led by Reps. Barney Frank (Mass.) and Peter W. Rodino Jr. (N.J.), made two concessions. They abandoned a committee-approved proposal to make the system permanent and agreed with Shaw to extend it for only five years. They also accepted an amendment offered by Rep. Dan Lungren (R-Calif.) to require all future independent counsels to work full time on their inquiries at a rate of $77,500 a year.

Independent counsels, usually chosen from the ranks of established attorneys, are now paid a per diem -- about $290 per day.

An amendment offered by Frank and approved on voice vote would make records of completed investigations subject to the Freedom of Information Act, under National Archives administration. The documents are now kept by the special three-judge U.S. Court of Appeals panel that appoints independent counsels and receives their findings.

Under the law, enacted in 1978, the attorney general, upon receipt of specific, credible information alleging crimes by a high-ranking official, is supposed to conduct a preliminary inquiry for no more than 90 days to determine if further investigation by an independent counsel is warranted.

Meese, however, has sometimes short-circuited the process by first having the Justice Department conduct a "threshold inquiry" to determine if the information is specific and credible enough to trigger the 90-day rule. Meese also has held that there were no grounds for further investigation of some high-ranking Justice Department officials because of "insufficient evidence of criminal intent" on their part.

The House bill specifically prohibits the attorney general from using such a "state of mind" finding as grounds for refusing to trigger the 90-day rule or failing to apply to the court for appointment of an independent counsel. The measure also makes clear that independent counsels, once appointed, can go directly to the special court for expansion of their prosecutorial jurisdiction. They now must get permission from the attorney general.

Court challenges to the system's constitutionality have piled up, but judges so far have rejected them. U.S. District Court Judge Thomas A. Flannery joined that group yesterday, refusing to dismiss an indictment against former Reagan White House aide Lyn Nofziger and his partner in a Washington consulting firm, Mark Bragg.