The Supreme Court agreed yesterday to decide whether judges may choose on their own to impose the death penalty after prosecutors decide not to seek capital punishment.

The court said it would hear the case of an Idaho man, Bryan Stuart Lankford, who was sentenced to death after being convicted of participating in the killing of two campers. The state did not seek the death penalty, instead recommending the minimum sentence available: life with the possibility of parole.

But the trial judge, without announcing his intention in advance, decided to impose the death sentence.

In urging the court to review the case, Lankford's lawyer argued that the proceeding had been "extraordinarily unfair" in that she was "affirmatively misled" into thinking she did not need to argue against the death penalty.

The state of Idaho, however, said the murder statute itself made clear that the death penalty was an option, giving Lankford "constitutionally adequate notice" of the potential punishment. The Idaho Supreme Court upheld the penalty in Lankford v. Idaho.

The court also said it would hear the case of a former psychologist at St. Elizabeths Hospital here who filed suit against his former supervisor for damaging his reputation and interfering with his ability to earn a living.

The case, Siegert v. Gilley, involves Frederick A. Siegert, who left St. Elizabeths in 1985 for a job with the Army after clashing with the supervisor, H. Melvyn Gilley.

He was unable to obtain staff privileges at an Army hospital in West Germany after Gilley, in response to an information request, said in a letter that Siegert was "inept, unethical" and "perhaps the least trustworthy individual" Gilley had encountered during his 13 years at St. Elizabeths.

Siegert filed for damages against Gilley, alleging Gilley had violated his constitutional rights. Defended by the government, Gilley argued that under previous Supreme Court decisions he enjoyed a limited immunity from such claims.

The federal appeals court here threw out the suit, ruling that Siegert had failed to specify direct evidence of illicit motives on Gilley's part, which would have overcome his immunity.

Noting the importance of shielding government officials from having to defend themselves against baseless claims, the court said Siegert was not entitled to conduct discovery -- the means of gathering information in civil lawsuits -- to obtain such evidence.

Siegert's lawyer, asking the court to hear the case, argued that the appeals court standard imposes "a hurdle not possible to jump." The Justice Department, opposing review, said "anything less" than the rule applied by the appeals court "would seriously undermine the significance" of the court's decisions granting limited immunity to government officials.

In other action yesterday, the court:

Let stand the racketeering convictions of a Northern Virginia couple and the seizure of bookstores and video rental stores they owned for selling obscene material. {Details on Page B5.}

Ruled that Georgia must obtain advance approval from the Justice Department or a federal court before creating new elected judgeships. Summarily affirming a lower court ruling, the court rejected Georgia's argument that the "pre-clearance" requirements of the Voting Rights Act do not apply to judgeships.

Let stand a ruling prohibiting Texas and 33 other states from regulating deceptive advertising by airlines about their fares. The appeals court in Mattox v. Trans World Airlines said such state rules were preempted by federal law.

Overturned a Minnesota man's federal conviction in Cary v. U.S. for burning an American flag during a 1988 demonstration and ordered a federal appeals court to reconsider the case in light of the decision last year striking down the federal flag-burning statute.

Refused to hear the case of two Illinois policemen who were disciplined for wearing earrings off-duty. The case is Rathert v. Peotone.