RICHMOND, DEC. 30 -- A federal appeals court upheld a Maryland Democratic Party rule that requires an equal number of male and female national convention delegates.

The 4th U.S. Circuit Court of Appeals reversed U.S. District Judge Walter E. Black Jr.'s ruling that the rule infringed on Nicholas Bachur Sr.'s fundamental right to vote.

The court also rejected Bachur's claim that the rule violates candidates' 14th Amendment rights to equal protection under the law.

The national party adopted a rule in 1976 requiring that the delegations from each state contain an equal number of men and women. The Maryland party adopted a plan to conform with that rule, which was intended to correct disproportionately low representation of women in the nominating process.

The rule required Bachur, a registered Democrat, to vote for four male and four female delegates.

The unanimous three-judge appeals panel ruled Tuesday that a political party has a right of political association protected by the First and 14th amendments, "and that right . . . carries with it the right to determine the party's own criteria for selection of delegates to its national convention."

The court said a political party's right may not be boundless, but the Supreme Court has not defined its limits. The appeals court said the Supreme Court had warned that "judicial intervention in this area has traditionally been approached with great caution and restraint."

In a 1981 Wisconsin case, the Supreme Court ruled that "the party had a First Amendment right to determine the makeup of a state's delegation to the national convention," appeals court Chief Judge Harrison L. Winter wrote.

Although Tuesday's ruling applies only to the Maryland case, lawyers and party officials believe it could have national implications. The New York and West Virginia Democratic parties had filed friend-of-the-court briefs arguing that the courts could not interfere with party rules.