The Supreme Court yesterday agreed to decide whether police officers who obtain a warrant to search a public place may search all persons who happen to be there.

The justices voted to hear arguments in a test case from Aurora, Ill., where a March 1, 1976, police reid on a tavern, the Aurora Tap, led to the conviction of Ventura Ybarra on a charge of heroin possession.

Lawyers for Ybarra want the justices to overturn his conviction, arguing that police violated Ybarra's constiutional protection against unreasonable searches when they subjected him to a body frisk.

Ybarra was one of about a dozen patrons at the bar when police officers investigating alleged drug trafficking raided the tavern.

Police did not suspect Ybarra of any crime, but decided to search all patrons for concealed weapons. Some heroin was found in Ybarra's possession.

At issue is an Illinois law that allows police officers to search all persons on the scene during a search granted by a court warrant -- even if the persons have not been or are not criminal suspects.

Accrding to an Illinois appeals court that rpheld Ybarra's conviction, similar lawa are on the books in Arizona, Kansas, Georgia and the District of Columbia.

Ybarra's appeal contends that the Illinois law violates the Fourth Amendment of the Constitution.

In other action:

The court opened the way for Florida murderer John Spenkelink to become the first person executed against his will in the United States since 1967.

The court declined for the third time in several years to review the Spenkelink case, and refused to consider new questions he raised about a subtle form of discrimination in capital punishment.

Spenkelink is the first Death Row inmate to exhaust all available state and federal appeals since the court ruled capital punishment constitutional in 1976.

Florida Gov. Bob Graham now must decide whether to sign the death warrant and set a decline for execution. That process, together with last-ditch efforts by defense lawyers, may take months.

The court agreed to review a lower court's ruling that the government says makes it too dificult to prove that a person has forfeited U.S. citizenship.

At issue is whether the government bears the burden of proving "by clear, convincing and unequivocal evidence" that a renunciation of citizenship was made voluntarily.

That was the standard laid down in a ruling by the 7th U.S. Circuit Court of Appeals last May.

Government lawyers say the standard should be the one contained in a 1961 law passed by Congress: that a person who renounces U.S. citizenship is presumed to have done so voluntarily unless a "preponderance of evidence" overccomes that presumption.

The 1961 law violated that portion of the Constitution granting citizenship to all persons born or naturalized in the United States by not providing enough protection against expatriation, the 7th Circuit court ruled.