Washington ? Federal enforcement of civil rights laws has dropped sharply since 1999 even though the level of complaints received by the Justice Department has remained relatively constant, according a study released Sunday.

Criminal charges alleging civil rights violations were brought last year against 84 defendants, down from 159 in 1999, according to Justice Department data analyzed by the Transactional Records Access Clearinghouse at Syracuse University.

In addition, the study found that the number of times the FBI or another federal investigative agency recommended prosecution in civil rights cases had fallen by more than one-third, from more than 3,000 in 1999 to just more than 1,900 last year. Federal court data also show the government has sought fewer sanctions against civil rights violators.

The study’s co-author, David Burnham of the clearinghouse, said the results showed that civil rights enforcement dropped across the board during President Bush’s first term in office.

The Justice Department enforces a wide range of civil rights laws ranging from guaranteeing fair housing access to prosecuting hate crimes.

“Collectively, some violators of the civil rights laws are not being dealt with by the government,” Burnham said. “They’ve declined by a huge number of cases. This trend, we think, is significant.”

It’s unlikely that the decline has occurred because fewer civil rights violations are occurring, the study suggests.

The number of complaints about possible violations received by the Justice Department has remained near 12,000 annually for each of the past five years.

The Justice Department had no comment about the study.