Winfred Brown, a 30-year-old drifter who spent six weeks in D.C. Jail last year in a case of mistaken identity, has filed a $7 million lawsuit against the District and federal governments.

The suit claims that prosecutors repeatedly ignored requests by Brown's attorney to compare his fingerprints with those of Johnny T. Jones, the man police and prosecutors insisted he was.

When a comparison by a private expert finally showed that Brown wasn't Jones, the suit says, a prosecutor handling the case said he had known for a week that the fingerprints didn't match even though Brown had not yet been released from jail.

The suit, filed late Tuesday in U.S. District Court here, accuses D.C. police and the U.S. attorney's office, which prosecutes criminal cases in Washington, of false arrest, false imprisonment, negligence, violations of civil rights and malicious prosecution, among other wrongs.

Brown's attorney, E. John Domingues, said Brown now lives in Dallas where he sells jewelry.

He was arrested Sept. 4, 1984. A police computer check indicated that Brown was Jones and was being sought on an arrest warrant for a destruction of property charge. He was jailed despite protests that he was the wrong man.

Several months after Brown's release, officials said the mistaken identity occurred because of a clerical error in which Jones was given a D.C. police identification number that had been assigned to Brown.

Yesterday, Alan Maness, a former special assistant U.S. attorney named in the suit, declined to comment on the case.

Royce C. Lamberth, chief of the civil division of the U.S. attorney's office, said the government may move to dismiss the suit because Brown has not yet filed an administrative complaint, which would have triggered an official investigation of his charges.

"Obviously, the allegations warrant close inquiry about what went wrong with the system," Lamberth said. "But what went wrong and whose responsibility it is, that's something which has not been determined."