District of Columbia government lawyers yesterday challenged the basis for a U.S. District Court ruling that police here routinely violated the constitutional rights of criminal defendants by not bringing them to court quickly enough after arrest.

At the same time, the D.C. corporation counsel's office said it would agree to a 12-hour time limit between arrest and a defendant's first appearance in court. Adoption of such a rule would give the District, along with Kentucky, the strictest time limit in the country.

The action by the corporation counsel's office came in response to a sharply critical ruling by Chief Judge William B. Byrant last May in which he said it normally should take no longer than 90 minutes for the police to process a defendant through the system and get him to court.

In August, after the city government asked for extra time to comply with Bryant's order to eliminate delays, he directed the police department to account strictly for any cases in which a defendant's court appearance was delayed for more than four hours.

After studying the problem, the corporation counsel's office filled a lengthy memorandum yesterday asking Bryant to consider a 12-hour standard. The city's lawyers also questioned, for the first time, the legal grounds for Bryant's opinion, and asked him not to issue any order that would apply to the D.C. Superior Court, where 95 percent of all the city's criminal cases are heard.

The remaining 5 percent of criminal cases are head in the U.S. District Court.

Basically, the corporation counsel's office argues that the issue of the appropriate time betweeen arrest and initial appearance in Superior Court is a matter of interpretation of procedural rules there and not a constitutional question.

It is within Bryant's discretion as a federal judge to defer to those Superior Court rules and abstain from issuing an order that would set a flat standard for the local court, the corporation counsel's office argued.

Any final order in the case should apply only to cases in the U.S. District Court, the corporation counsel's office said.

Bryant's order stemmed from a class action suit brought by the American Civil Liberties Union Fund of the National Capitol Area against the police department.

In the memorandum filed yesterday, the city lawyers said they "recognize the important policy considerations" raised in the lawsuit, however, even as it pertains to the Superior Court. So, they argued, if Bryant did not accept their legal challenge to his decision. They would "compromise" on a 12-hour standard.

Studies have shown that the police process 99 percent of all cases within 12 hours but 40 percent of the felcony cases and 10 percent of the misdemeanor cases "cannot be delivered to the court because the court is not open," the corporation counsel contended in its memorandum.

The studies of police processing procedures here were conducted for the city government by the police department itself and by the Institute for Law and Social Research, a Washington-based research group.

The INSLAW study found that the majority of all cases are now processed in less than four hours and that more than 90 percent of felony and misdemanor cases are processed within seven hours. A major factor in determining the total length of time for processing a defendant is the hours the court is available to hear the cases, the study said.

The disput raised by the ACLU in its lawsuit, therefore, is difficult to resolve simply within the police process since major delays occur in the court itself, the corporation counsel's office argued.

Generally, police processing includes talking fingerprints, photographs and the completion of paperwork on suspects. In suggesting the 12-hour standard, the city's lawyers argued that some complicated cases would require longer investigation before the defendant's first appearance in court.

"Considering the open hours as they presently exist in both the D.C. Superior Court and the U.S. District Court, it is unlikely that a shorter time limitation (under 12 hours) would prove significantly effectual in any case," the corporation counsel's office said in a memorandum signed by Acting D.C. Corporation Counsel Louis P. Robbins and Deputy Corporation Counsel Geoffrey M. Alprin, chief of the criminal division.