A former U.S. representative from Kentucky who came under scrutiny in the House Bank scandal pleaded guilty yesterday to federal charges that he obstructed investigators by ordering an aide to destroy campaign records after they were reported stolen in a phony break-in at his congressional district office.

Carroll Hubbard Jr., 56, a nine-term Democrat who worked undercover for the FBI after being caught in the bank scandal in 1991, also pleaded guilty to two other felonies in U.S. District Court in Washington yesterday.

Hubbard, who told The Washington Post in December that he had hoped to stave off prosecution by working for the FBI, admitted that he misappropriated more than $50,000 in campaign money for illegal use and ordered members of his congressional staff to perform personal and political tasks for him while they were being paid by the government.

Among other crimes, he admitted aiding his wife's failed congressional campaign by illegally shifting thousands of dollars from his political fund to hers. The Justice Department said in court that Hubbard tried to conceal the transactions by funneling the money through several banks in Kentucky and the House Bank in Washington.

Hubbard, whose 18-year career ended with a Democratic primary defeat in 1992, is to be sentenced June 16 on charges punishable by a total maximum 20 years in prison. His wife, Carol Brown Hubbard, 53, pleaded guilty yesterday to lesser offenses. Prosecutor Thomas J. Eicher said he plans to ask the judge in the case to spare Carol Hubbard a prison term.

Hubbard came under FBI scrutiny in 1991 after it was disclosed to the public that many members of Congress had routinely overdrawn their House Bank accounts without being penalized. Hubbard's 152 overdrafts ranked 15th in number of checks among the 325 House members who overdrew their accounts.

By December 1992, federal investigators also had begun looking into Hubbard's use of his staff and campaign funds.

Eicher told U.S. District Judge Louis Oberdorfer yesterday that from 1990 to 1992, Hubbard siphoned tens of thousands of dollars out of his campaign fund and put the money to personal use in a variety of ways, including paying gas, heating and credit card bills, school tuition for a daughter and his former wife's cable television bill.

In an effort to rattle his political opponents, Hubbard instructed staff members to overstate the amount of cash in his campaign fund when filing federal election finance reports, Eicher said.

In November 1992, according to the government, "Hubbard directed one of his employees to shred and throw away documents that had been subpoenaed" by a grand jury. "Prior to that, Hubbard had staged a burglary at one of his offices to make it appear that his House Bank and campaign records had been stolen."

In July 1992, Eicher said, Hubbard took $15,000 from his campaign fund, channeled it through several banks, including the House Bank, then gave money to various associates in Kentucky. The recipients then wrote backdated checks to Carol Brown Hubbard's congressional campaign.

Hubbard also put his congressional office staff to work on his and his wife's 1992 campaigns, Eicher said. The staff members, working on government time, arranged schedules, solicited contributions and campaigned in Kentucky, using assumed names, Eicher said. He said the staff members believed they would lose their jobs if they did not comply.

The aides also escorted Hubbard's elderly mother on trips -- to a Baptist convention, among other places -- and filed false government expense reports to cover their costs, according to Eicher.

Hubbard spoke only briefly in court yesterday, telling Oberdorfer that he was "in substantial agreement with the allegations," but that some of Eicher's details were incorrect.

In The Post interview, Hubbard said he had hoped to avoid prosecution by working undercover for the FBI last year and that he thought he was going to help in investigations of Libyan agents and lobbyists in the United States.

Hubbard said an FBI agent also spoke of plans for an "Abscam II" investigation, referring to an undercover operation in the early 1980s in which six House members and a senator were convicted on corruption charges.

But prosecutor Eicher, chief of the Justice Department's House Bank task force, said yesterday that "no Abscam-type investigation of Congress is being contemplated, nor was one contemplated."

The FBI used Hubbard mainly in investigations of several of his associates in Kentucky. He said agents gave him the code name Elmer Fudd, strapped a hidden recorder to his body on some occasions, and at other times instructed him to secretly tape telephone conversations.