In his current federal obstruction-of-justice trial, former Maryland state senator Clarence M. Mitchell III has filed an affidavit from a former FBI informant that could give credence to what many people thought were self-serving, paranoid even, expressions from black elected officials.

According to the affidavit, signed by Hirsch Friedman, 45, a former FBI informant in Atlanta, the FBI had an "unofficial policy" in the late 1970s and early 1980s to investigate "without probable cause prominent elected and appointed black officials in major metropolitan areas throughout the United States."

Friedman, now an Atlanta lawyer and businessman, said the policy was called Fruehmenschen, a German word that translates roughly to "primitive man or early man," and was based on "the assumption by the FBI that black officials were intellectually and socially incapable of governing major governmental organizations and institutions."

Last week, when a reporter asked Justice Department spokesman John Russell about Friedman's allegations, he said, "I never heard of any such policy." John C. McAvoy, an FBI agent in the Atlanta field office who, according to Friedman, used the term repeatedly, declined to comment when he was reached in Atlanta.

While I am certainly neither drawing conclusions nor making protestations of the guilt or innocence of anyone, it certainly seems that these are serious new allegations to which the response has thus far been inadequate. Indeed, it's one thing for the Justice Department to say, "I never heard of any such policy," but it is another to try to find out if such a policy existed and really get to the bottom of the situation.

Indeed, Friedman's nine-page affidavit had no absence of detail. For example, he noted that probes were specifically targeted. "I understood that over a dozen indictable cases against white appointed officials and others in the northern district of Georgia were dropped . . . while great effort was put forth in connection with the Fruehmenschen policy," he said.

"An upshot of the . . . policy in Atlanta," Friedman continued, "was the investigation generally referred to in the Atlanta FBI field office as Blue Eyes, Green Eyes and Brown Eyes. This investigation referred to Blue Eyes, Eldrin Bell, a top-ranking black police official in Atlanta who has blue eyes; Green Eyes, Maynard Jackson, then-mayor of Atlanta who is black and has green eyes, and Brown Eyes, A. Reginald Eaves, a black Fulton County commissioner.

Three months ago, Eaves was indicted by a federal grand jury in Atlanta on charges of taking payoffs, some from FBI agents posing as land developers. The indictments came after a four-year investigation.

As for Friedman, it's interesting that his undercover work with the FBI came to an abrupt end. He claimed that the loss of a leg occurred in a 1982 car-bombing when the FBI failed to protect him in undercover work allegedly involving organized crime figures, and he is involved in a $20 million lawsuit against the bureau. A federal judge ruled that the FBI was not responsible, but Friedman has appealed the ruling.

My point is not to attempt to exonerate Eaves, Mitchell or anyone else accused of a crime -- that is a job for the courts. But when it comes to the FBI and black leaders, the record has not been particularly exemplary. It was nearly a dozen years ago that the Senate Intelligence Committee disclosed, in stark detail, the FBI's shadowing, wiretapping and later bugging of the Rev. Martin Luther King Jr. in the 1960s. That campaign was "marked by extreme personal vindictiveness," the committee said in a staff report, and it was driven by the almost pathological animosity of then-FBI Director J. Edgar Hoover toward King.

Not only are the origins of the campaign against King in some dispute, but also the FBI still refuses to produce the records because it contends that in the interest of national security its sources should remain confidential.

As the nation pauses for today's celebration of King's birthday, it is the height of irony that these disclosures about questionable FBI activities toward black leaders have surfaced. Indeed, cynics might say the old policies are alive and well.

The allegations against the FBI may or may not be true. But they are deeply serious and deserve a full investigation, not a back-of-the-hand dismissal as the Justice Department has done so far. For what is at stake here is the integrity of the American system of justice, and that is of concern not just to black elected officials and other black people, but to all Americans.