As he waits in Tunisia and looks back at the events of 2010 that led to his arrest and deportation, Moones Mellouli may wish he had done things differently, such as not wearing socks containing Adderall.

Mellouli's case has, however, led to a U.S. Supreme Court decision that could mean relief for many immigrants facing deportation for minor drug-related convictions. The victory is shared with a distinctive collaboration of a new University of Minnesota Law School immigration law center, area law firms and immigration nonprofits that represented him.

In a 7-2 decision on June 1, the court ruled that the federal government could not deport Mellouli, a permanent resident, for a conviction in Kansas of possessing drug paraphernalia, an offense not listed in federal law.

For the Center for New Americans, it is a major win and validation of its mission to provide legal aid to immigrant communities. Attorneys at the center had been checking online for months for word of a decision, until excited yells suddenly punctured the office quiet last week.

"This case is the fourth [decision] in a line at the Supreme Court that rejects attempts by the immigration authorities to read the immigration law more broadly and capture more convictions than the immigration law really does," said Kate Evans, an attorney and teaching fellow at the center who worked on the case.

For Mellouli, 33, the ruling means he can reunite with his American fiancée of nearly four years, and begin putting the pieces of his former life back together. But the effect is expected to be much broader.

"I think it can affect thousands of people," Kevin Johnson, dean of the University of California-Davis Law School, said in an interview.

Mellouli arrived in the United States on a student visa in 2004. He earned two master's degrees and then worked as an actuary and taught mathematics. In 2011, he became a lawful permanent resident.

In 2010, he was arrested in Kansas for driving under the influence and having a suspended license. Mellouli pleaded guilty to DWI and possessing not drugs, but drug paraphernalia in the form of a sock containing four orange Adderall pills found in a post-arrest search. Adderall is prescribed to treat hyperactivity but is often used by people without a prescription to stay awake.

No jail time before ICE

Mellouli received a suspended sentence and one year of probation. In 2012, he was arrested by U.S. Immigration and Customs Enforcement (ICE) officers and deported by an immigration judge, whose order was upheld by the Board of Immigration Appeals and the Eighth Circuit Court of Appeals.

Established just two years ago, the Center for New Americans took on Mellouli's appeal. More than 35 attorneys in Minnesota and nationally went to work on it. The center regularly partners with the law firms of Faegre Baker Daniels, Robins Kaplan and Dorsey & Whitney, along with the Immigrant Law Center of Minnesota, the Advocates for Human Rights and Mid-Minnesota Legal Aid.

Before the Supreme Court was the question of whether the federal government can deport legal permanent residents for the minor offense of possessing drug paraphernalia not covered under the Federal Controlled Substances Act. While Kansas law considers a container — or sock, in this case — to be drug paraphernalia, the government can only deport those whose conviction is related to a federally controlled substance.

Writing for the court's majority last week, Justice Ruth Bader Ginsburg wrote, "We therefore reject the argument that any drug offense renders an alien removable, without regard to the appearance of the drug on a [Controlled Substances Act list]."

Justices Clarence Thomas and Samuel Alito dissented.

Biggest case so far

The Mellouli case has been the biggest the center has handled, said Evans. Its successful collaboration may mean a new model for handling such immigration cases, which can be time-consuming and require considerable resources.

The center was established with part of a $9 million donation by the Robina Foundation. The law school bills it as the first program of its kind. It's home to three immigration clinics and an outreach program that allows law students to work on immigration issues.

"It was an incredible experience I think for everybody," said recent graduate Julia Decker.

Mellouli served no jail time for his conviction, but he was detained six months in a county jail in Versailles, Mo., during his immigration proceedings. He was deemed ineligible for cancellation of removal because he had not been a lawful permanent resident for five years. The center is working with authorities to restore his previous immigration status to allow for his return.

According to ICE data for fiscal year 2015, between October and March 7, 887 people were deported by its Twin Cities field office, which covers Minnesota, Iowa, Nebraska, North Dakota and South Dakota. About 79 percent of those cases involved immigrants with criminal ­convictions.

Some immigration attorneys welcomed the decision as a needed development in immigration law by forcing immigration courts to treat possession of illegal drugs the same as possession of drug paraphernalia.

Susan Cohen, a Boston immigration lawyer active in the American Immigration Lawyers Association, wrote in the National Law Review that the decision took the "Board of Immigration Appeals to task for routinely applying inconsistent standards in its decisionmaking."

Nonetheless, the Mellouli decision, said Brian Aust, a Minneapolis immigration attorney, should not be treated as a license for noncitizens to skirt drug laws. "Don't take this as an invitation to get caught with drugs," he advised. "Drugs can still result in the harsh consequence of removal."

Marcus E. Howard • 612-673-1720 Twitter: @MarcusEHoward