Supreme Court justices wrestled Tuesday with the question of whether convictions for minor crimes should force immigrants' deportation, the first case in a term expected to make clearer the court's direction under Chief Justice John Roberts.

Thousands of immigrants who have run afoul of the law, some for possessing small amounts of drugs, could be affected by the outcome of Tuesday's arguments.

The second year of Roberts' tenure began with little drama, just a brief welcome to visiting jurists from India.

Eight justices, all but the habitually quiet Clarence Thomas, took part in questioning lawyers from both sides as the Bush administration asserted that immigrants convicted of state drug felonies are deportable even if the same crimes are considered only misdemeanors under federal law.

Jose Antonio Lopez, of Sioux Falls, S.D., was ordered deported after he pleaded guilty to aiding and abetting possession of cocaine. The crime is a felony under South Dakota state law, but only a misdemeanor under the federal Controlled Substances Act if it is a first offense for cocaine possession, as it was in Lopez' case.

"The problem here is that state law and federal law are at odds in determining the gravity of the offense," Justice David Souter said.

Several justices said they were troubled that immigration authorities would treat differently two people who commit the same crime in different states that hand out different penalties. Federal appeals courts have split over interpreting the immigration law at issue in the case.

An immigration judge and review panel as well as a federal appeals court all concluded that Lopez' crime should be considered an aggravated felony, which severely limits immigrants' ability to fight off deportation, be granted asylum or become naturalized U.S. citizens.

Lopez, a 16-year permanent U.S. resident, already has been deported to Mexico, but could return to his wife and two children, who are U.S. citizens, if the court rules in his favor, said Benita Jain, a staff attorney with the New York State Defenders Association.

Even then, Lopez still could face deportation, but an immigration judge would have discretion to allow him to remain in the United States.

Justices were more skeptical of the claims of another immigrant, who had been in the United States illegally and whose case was considered along with Lopez'.

Reymundo Toledo-Flores, a Mexican national, is objecting to having his latest conviction for illegally entering the United States classified an aggravated felony.

Since he is contesting his prison term, rather than his deportation, justices wondered why they should even be dealing with Toledo-Flores' case now that he has served his sentence and has been returned to Mexico.

Toledo-Flores remains on supervised release, a kind of probation, said his lawyer, Timothy Crooks of Houston. Refraining from alcohol is one of the conditions of his release, Crooks said.

That claim was too much for Roberts and Justice Antonin Scalia. "There is no supervised release of people outside the United States," Roberts said.

Scalia added: "Nobody thinks your client is abstaining from tequila down in Mexico because he's on supervised release in the United States."

Death Sentence Case

Justices also heard arguments Tuesday in a California death penalty case that could further demonstrate an increasingly hardened split on the court over executions.

A decision whether to reinstate a death sentence for Fernando Belmontes in a 25-year-old California murder could affect a handful of other cases.

Belmontes beat 19-year-old Steacy McConnell to death with a dumbbell bar in the burglary of her Victor, Calif., home. He was convicted of the crime and sentenced to death, a decision upheld by state courts and a federal judge.

The 9th Circuit U.S. Court of Appeals, however, has twice thrown out the death sentence, the second time after the Supreme Court told it to reconsider Belmontes' sentence under a recent decision that restored the death penalty in another California murder case.

The appeals court said the trial judge misled jurors about whether they could consider the prospect that Belmontes could live a productive life behind bars based on his good behavior during an earlier commitment to a California correctional facility for youth.

One change that took effect Tuesday was the posting of transcripts of the oral arguments on the Supreme Court's Web site a few hours after they took place.

The consolidated immigration case is Lopez v. Gonzales, 05-547, Toledo-Flores v. United States, 05-7664.

The California death penalty case is Ayers v. Belmontes, 05-493.