Updated

New rules on FBI investigations of national security cases should be delayed, top Senate Judiciary Committee members said Monday, raising concerns that ethnic or racial groups could be targeted despite no evidence of wrongdoing.

In a letter to Attorney General Michael Mukasey, the senators called for congressional hearings on the rules before they are finalized. They suggested delaying the rules — known as the attorney general guidelines — until FBI Director Robert Mueller appears before the panel Sept. 17.

Judiciary Chairman Patrick Leahy, D-Vt., and Sen. Arlen Specter of Pennsylvania, the panel's top Republican, called the guidelines a "laudatory effort to ensure that front-line agents are given clear rules to follow in pursuit of their investigations."

"Nevertheless, efforts to harmonize the rules governing criminal and national security matters also raise potential civil liberties concerns, given the broader latitude currently given to investigators to consider race and ethnicity in national security matters," Leahy and Specter wrote.

They added: "The important aims of the guidelines, and their potential implications for civil liberties, require a meaningful dialogue between Congress and DOJ."

DOJ stands for the Department of Justice, which oversees the FBI.

The rules are expected to be finalized later this week or early next week. Justice spokesman Peter Carr said Monday that the department is reviewing the letter.

"We continue to discuss this with Congress, and we are carefully reviewing the suggestions we have received from these discussions," Carr said.

The planned changes, first reported last month by The Associated Press, is part of an update of Justice Department policies amid the FBI's transition from a traditional crime-fighting agency to one whose top mission is to protect America from terrorist attacks.

Currently, FBI agents need specific reasons — such as evidence or allegations that a law probably has been violated — to investigate U.S. citizens and legal residents. The new policy, law enforcement officials have told AP, would let agents open preliminary terrorism investigations after mining public records and intelligence to build a profile of traits that, taken together, were deemed suspicious.

Among the factors that could make someone subject to an investigation is travel to regions of the world known for terrorist activity, access to weapons or military training, along with the person's race or ethnicity.

Mukasey repeatedly has said that investigations will not be opened solely on the basis of race, ethnicity, religion or other traits that could amount to unconstitutional profiling. He has declined to answer whether the new rules could change the standards for opening an investigation or otherwise allow FBI to scrutinize Americans without evidence of a crime.

The Justice Department is briefing lawmakers and interest groups about the guidelines this week.