The Justice Department yesterday unveiled what was termed a compromise plan balanced to protect both investigators' access to needed bank records and individual rights to privacy.

In a break with other law enforcement agencies and the department's past opposition to such proposed legislation Deputy Attorney General Benjamin R. Civiletti told a Senate Banking subcommittee that Justice now agrees that citizens should be notified and given a chance to object when investigators are seeking access to their financial records.

But he also outlined several changes Justice recommended so such access, the "lifeblood" of successful investigations of white-collar and organized crime, is not unduly hampered.

The proposed legislation, sponsored by Sen. Alan Cranston (D-Calif.) is designed to protect personal privacy rights in the wake of a 1976 Supreme Court decision. In that case the court ruled that bank records belong to the bank, not the customer, so the person would have no inherent right to expect the records to remain private.

Under present practice, federal investigators seek grand jury subpoenas for financial records or, on an informal basis, simply ask bankers to co-operate without the customer's knowledge.

The Justice Department's new position is the product of several months on study by an internal task force and was praised yesterday by several congressional students of the privacy issue.

The department's "tightrope-walking" stance was evident yesterday as other witnesses criticized the Senate bill as too strong or too weak.

Securities and Exchange Commission Chairman Harold M. Williams testified that the bill would place an "impossible burden" on the agency because persons or corporations under investigation would "shelter" their records for months by filing objections to SEC subpoenas.

Irving M. Pollack, an SEC commissioner and former enforcement chief, said that he had never seen anything as "detrimental" as the bill's provisions in his 30 years as an enforcement official. "I am fearful this bill will really cripple (the SEC)," he said.

New Jersey Attorney General John J. Degnan also strongly opposed the bill, while representatives of the American Civil Liberties Union and the Privacy Journal, a Washington-based newsletter, said the proposals fell short of protecting individuals because they didn't cover credit card or phone records or apply to private investigators as well as government agencies.

Civiletti said Justice could support a bill that allowed the government to bypass the prenotice provisions in emergency situations where notice might lead as target of an investigation to flee or to destroy evidence.

He also said the bill should be amended to make bank customers file a court motion rather that what he said was often a "frivolous" written objection. He noted that of 476 objections to IRS summons filed under a recent tax revision act, none was upheld.

Civilletti said the department was pleased that the bill exempted grand jury subpoenas from the proposed notice requirements, but added that targets of foreign intelligence investigations also should be exempt.