The Supreme Court agreed yesterday to decide whether a Nevada lawyer's rights were violated when state bar officials reprimanded him for holding a news conference proclaiming his client's innocence.

The court said it would hear the case of Dominic Gentile, who was issued a private reprimand by Nevada bar officials for his comments about client Grady Sanders, who was ultimately acquitted of stealing money and drugs from a safe deposit box used by Las Vegas police.

On the day of Sanders's 1988 arraignment, Gentile told reporters on the courthouse steps that Sanders was "an innnocent person" and that there was "far more evidence" that the material was taken by a Las Vegas police officer.

Nevada bar officials later charged Gentile with violating a state rule, modeled on American Bar Association ethics rules, that prohibits lawyers from making out-of-court statements they should know are likely to prejudice the case. Twenty-three other states have similar rules limiting lawyers' public statements about pending cases.

The Nevada Supreme Court rejected Gentile's argument that the reprimand violated his First Amendment rights of free speech. In asking the high court to hear the case, Gentile's lawyer said the court had never directly addressed the the limits the First Amendment places on states' ability to regulate lawyers' speech about pending cases.

He said the statements for which Gentile was punished were "at the core of First Amendment protection: . . . A public press conference about police misconduct, in which the speaker had a sound factual basis for his measured allegations."

State officials said the rule "promotes the trial of cases in the courtroom rather than in the airwaves" and that the news conference was more like "a forum for advancing a lawyer's personal interests in fame and notoriety than in exposing police misconduct."

In other action, the court rejected several challenges by state and local officials in voting rights cases. Without opinion, the justices upheld a lower court ruling in Clinton v. Jeffers finding that Arkansas' 1981 reapportionment plan discriminated against black voters and creating new black-majority districts.

The case was one of the first to reach the court in which its 1986 voting rights ruling involving at-large districts was applied to test the legality of single-member districts, and civil rights lawyers had feared the court might use the case to retreat from the 1986 ruling.