WASHINGTON - The Supreme Court on Tuesday rejected the White House's aggressive use of immigration laws to expel legal immigrants for minor drug crimes, a decision that could spare thousands from being deported.

Immigrants'-rights lawyers said the 8-1 decision would allow non-citizens who have otherwise clean records to appeal to immigration judges to stay in this country, despite a past drug conviction.

"This ensures these lawful residents will have their day in court," said Benita Jain, a lawyer for the New York State Defenders Association.

Since 1996, the more than 12 million legal immigrants in the United States have been subject to mandatory deportation if they are guilty of an "aggravated felony," including a "drug trafficking crime." Four years ago, the government expanded the reach of this law to include state drug crimes that can result in a one year in jail, even if the offense is simple drug possession.

In Tuesday's decision, the court said that broad interpretation ignored the plain words of the law. Noting Humpty Dumpty's use of words to mean whatever he wanted them to mean in Lewis Carroll's Through the Looking-Glass, the justices said it did not make sense to interpret the words "aggravated felony" and "drug trafficking crime" to mean simple drug possession.

Justice David H. Souter, who wrote the opinion, said the government's interpretation was incoherent.

The court said the automatic deportation rule should be triggered only by drug offenses that are the equivalent of drug crimes "punishable as a felony under federal law."

The decision reopened the case of Jose Antonio Lopez, an immigrant from Mexico who had lived as a permanent resident of South Dakota since 1990. He was married, has two kids and had owned a store.

The 1996 immigration law remains controversial, because it requires a mandatory deportation for certain offenses, regardless of circumstances.

The ruling does not shield immigrants who commit minor drug crimes from being deported in all instances. However, without the trigger of the automatic deportation rule, they can seek relief from an immigration judge.

PHOENIX (AP) -- A judge on Tuesday overturned Arizona's first jury conviction of an illegal immigrant charged as a conspirator under the state's smuggling law.

The 16-month-old law targets immigrant smugglers, but Maricopa County Attorney Andrew Thomas says those who paid to be sneaked into the country can also be charged as conspirators to the crime.

Attorneys on both sides said the ruling won't apply to other cases prosecuted under the conspiracy theory. Prosecutors plan to appeal the decision, and an appeals court could issue a ruling that could potentially bind lower-court judges considering similar cases.

The judge who presided over the October trial of 28-year-old Adolfo Guzman-Garcia ruled Tuesday that while the immigrant had paid to be sneaked into the country, there was no evidence presented showing he had agreed with another person to commit human smuggling.

Immigrant advocates have said the law was never meant to be used against the customers of smugglers. Thomas said his approach was needed for holding illegal immigrants accountable.

Arizonans are frustrated with the state's role as the busiest illegal gateway into the country. More than 160 people - most of whom were the customers of smugglers - were convicted in Maricopa County under the law.

Jose Antonio Colon, the attorney for Guzman-Garcia, said the ruling underscores a major flaw in the prosecutor's approach in charging rank-and-file immigrants as conspirators.

"This is a red flag that we have something wrong with these cases, and we need to fix them," Colon said.

Thomas said his conspiracy approach is legally sound and the latest ruling was a unique interpretation by a judge who had previously decided there was enough evidence for the case to go to jury. "This one is a curveball," Thomas said.

The latest ruling came from Maricopa County Superior Court Judge Thomas O'Toole, who had upheld the law earlier this year after defense attorneys said prosecutors were overreaching and questioned its constitutionality.

O'Toole, near the end of a trial in July, also dismissed the cases against two Mexican men who were charged with conspiring to commit human smuggling. The judge had said prosecutors didn't provide substantial evidence that two or more immigrants had agreed to be smuggled.

Gary Lowenthal, an Arizona State University law professor who specializes in criminal law, said the judge's decision to acquit Guzman-Garcia allows appeals courts to decide the issue.

"I'm not saying that was his motivation, but that certainly is the impact of his decision," Lowenthal said.

Authorities said Guzman-Garcia and 10 other men from Mexico were arrested in May when the truck they were traveling in was spotted speeding south of Phoenix.

Once a sheriff's deputy prompted the truck to pull over, the driver and occupants fled on foot into the desert. The smuggler was never caught, authorities said.