New York real estate developer Howard Milstein decided suddenly yesterday to switch courthouses in his legal dispute with former Redskins president John Kent Cooke over Milstein's unsuccessful bid to buy the franchise.

His attorneys said they have decided to move the case from U.S. District Court to D.C. Superior Court to avoid legal questions about jurisdiction.

Jonathan D. Schiller, an attorney for Milstein, said Cooke and former Redskins general manager Charley Casserly will remain defendants in the lawsuit, which alleges the two conspired to illegally thwart Milstein's bid for the team. Cooke and Casserly have denied wrongdoing.

Cooke, the son of the late Jack Kent Cooke, had contended the federal lawsuit could not move forward because he had moved to Bermuda by the time it was filed in May. U.S. District Judge Emmet G. Sullivan had scheduled a hearing for today on the matter. Cooke had planned to testify that he left Washington for Bermuda last March with no intention of returning.

Had Sullivan ruled that Cooke was not a D.C. resident last May, the claim against him would have been dismissed on jurisdictional grounds. Residency is not an issue if the case is filed in D.C. Superior Court, Schiller said.

Cooke's attorney, Joseph M. Hassett, has agreed not to challenge jurisdiction there, so the case now can move toward trial. Cooke issued a statement yesterday saying the matter didn't belong in any courthouse: "This suit should never have been brought, and this should be the end of it."

Milstein's suit alleges Cooke and Casserly unfairly conspired with allies in the National Football League to doom his $800 million bid for the team, even though Milstein was the top choice of trustees controlling Jack Kent Cooke's estate, in hopes that John Kent Cooke would emerge as the owner. Daniel M. Snyder, a former partner of Milstein's, ultimately got the team.

Sources familiar with the case said Cooke also faced risks had Sullivan gone forward with the hearing. By moving to Bermuda, Cooke put himself in position to avoid paying D.C. capital gains taxes on his share of proceeds from the 10 percent interest he had in the team. Had Sullivan found that Cooke still was a D.C. resident, Cooke could have faced tax implications.

The case took an even nastier tone over the last week, with attorneys for Cooke alleging in court papers that a representative of Milstein's had traveled to Bermuda, "misrepresented himself and surreptitiously recorded his conversation with Mr. Cooke." Casserly's attorneys said in court filings that their client feared "he has been subject to similar surveillance."

Despite protests from Milstein's attorneys, Sullivan agreed to permit the attorneys to conduct a sworn deposition of the man in Washington last Friday. The issue likely would have emerged at the hearing.

CAPTION: Howard Milstein assembled an $800 million offer but was unable to buy the Redskins.