Officials at Virginia's troubled Mecklenburg Correctional Center apparently violated state law by wiretapping telephone calls of death row inmates, the state attorney general's office said yesterday.

The wiretaps occurred over a month and were part of an investigation triggered by fears of a second major escape from the controversial prison. The intercepted calls included about a dozen conversations between inmates and their lawyers, which state officials said should have been confidential.

In all, about 75 calls were taped between Dec. 18 and Jan. 21, when a visiting assistant attorney general happened to learn of the recording device and complained, according to government officials.

Under Virginia law, wiretaps can be approved by state judges only after approval by the state attorney general's office and only for investigation of a handful of serious crimes. Prison escape is not one of the crimes covered, said David Hathcock, a spokesman for state Attorney General Gerald L. Baliles.

State police are investigating the recordings and have seized tapes and documents from the prison, officials said.

An attorney for the American Civil Liberties Union, which has successfully sued Virginia over its corrections policies, said the wiretaps also may have violated federal law. If sued under federal law, the state could be forced to pay damages up to $75,000 depending on the number of persons and conversations that were improperly recorded, said Alvin J. Bronstein, director of the ACLU's National Prison Project.

"It's outrageous," said Bronstein. His organization recently went back into federal court in Richmond, charging that Virginia has failed to live up to a 1983 consent decree mandating changes in the way Mecklenburg is run.

Neither the corrections department's new director, Allyn R. Sielaff, nor Mecklenburg's new warden, Toni V. Bair, knew about the recordings, correction officials said yesterday. Bair personally unplugged the device several days after the unnamed state lawyer told him about it, the officials said.

Hathcock said a court order for the wiretaps was signed Nov. 30 by retired Mecklenburg Circuit Court Judge C. Meredith Dortch, who serves part time. The court order was sought by Wesley Terry, a veteran internal affairs investigator for the corrections department, according to government sources. Terry could not be reached for comment.

Officials said yesterday there was a dispute over whether Dortch's order authorized the wiretaps of actual conversations or was limited to the less restrictive telephone "traps," which only record telephone numbers called or received.

Hathcock said the prison officials were concerned about a potential escape from Mecklenburg, but said that is not sufficient grounds under the state's restrictive law for a wiretap. They are allowed in cases of suspected extortion, bribery, kidnaping, murder or felonious drug trafficking, officials said.

The rural Southside prison was the scene May 31 of the escape of six inmates, the largest death row escape in U.S. history. All eventually were recaptured. The incident has sparked nearly a year of investigations into prison operations, which Gov. Charles S. Robb has called the state's "number one problem."

Bronstein, who praised the reaction of Baliles and Sielaff in stopping the taps, said wiretapping lawyer-client conversations is a violation of federal law and said "it certainly appears to be a violation" of a ruling last October by U.S. District Court Judge Robert R. Merhige.

Merhige, who then ordered the department to quit interfering with attorneys trying to see their clients, sharply criticized the department at the time for using "public relations gimmickry" to raise fears about security in an attempt to limit the access of attorneys to Mecklenburg.

Bronstein said he sent Baliles a telegram demanding that the state preserve all tape recordings and log books involved in the wiretap "for my inspection."