A coalition of city officials and women's advocacy groups is lobbying the District to change the way it defines fatherhood.

At stake, they say, are millions of dollars in unpaid child support and $2.5 million in federal money the city could lose unless it dramatically reduces its massive backlog of child support cases by next fall.

The primary reason for the backlog is that the courts are being flooded with paternity cases and the U.S. Marshal's Service does not actively pursue delinquent fathers who fail to show up in court, said Nkechi Taifa, of the Women's Legal Defense Fund.

Sixty-six percent of the babies born in the District last year were born to unmarried mothers, according to city records. And of District mothers seeking unpaid child support, 95 percent must prove paternity, Taifa said.

To do that, the mothers must bring the father to court, even if the child's birth certificate says he is the father and even if the man admits he is the father.

The word on the street, Taifa said, is "if you don't want to pay any child support, simply don't show up in court."

Advocates, led by the Women's Legal Defense Fund, are asking the D.C. Council to pass legislation to allow the voluntary acknowledgement of paternity to have the same effect as a court judgment.

Despite aggressive efforts in the past year, including a complaint hot line, to reduce the city's backlog of child support cases, the city still has a backlog of more than 19,000 cases, said Irma Neal, chief of the D.C. Office of Paternity and Child Support Enforcement.

In recent years, the federal government has been pressing jurisdictions to increase the number of men who pay child support to reduce the number of families receiving welfare, Taifa said.

Since 1985, the District has been fined more than $5 million for its failure to respond adequately. The federal government has stipulated that if the District does not reduce its backlog of child support cases by 75 percent by next October, it would cut the city's share of Aid for Dependent Children money by as much as $2.5 million.

Neal said her office, which receives 600 cases a month, will not be able to reduce the backlog unless paternity can be decided without going to court.

Although men in other states also must go to court, the requirement is a burden in the District because of city's "huge percentage of out-of-wedlock births," Taifa said.

Some women's advocates say city laws should be changed to make it possible to establish paternity by default if a father fails to appear in court. And they propose shifting authority for warrants in such cases from the U.S. Marshal's Service to the D.C. police. In most places, local sheriffs serve such warrants.

District police said they would not comment on the proposal until they can review it.

From January through October, 1,072 paternity bench warrants were issued by a judge, but only 350 people have come to court in response to letters from the city or the U.S. Marshal's Service, according to city records. More than 670 are outstanding.

"I can't remember when the marshals have actually gone out and apprehended anybody," said Arlene Robinson, who heads the legal arm of the District's child support enforcement program.

At the U.S. Marshal's Service, Chief Deputy Richard Oakcrum said his office has been struggling to keep up with the dramatic increase in drug-related arrests and that paternity bench warrants must be "put near the bottom" of the priority list.

Christopher Herrling, deputy director of legal operations at the Legal Aid Society of D.C., said men could benefit if a voluntary acknowledgement of paternity is legally accepted. Now, unless he goes to court to establish paternity, a father of a child born out of wedlock has no visiting rights, can't list the child as a dependent on a health insurance policy and won't be recognized as a father if he wants to enroll his child in school, he said.