A US appeals court has upheld a ruling that Microsoft can't be forced to give the Department of Justice access to customer emails stored outside the country.
In a 4-4 split, the Second Circuit Court of Appeals declined to reconsider its July decision denying the DOJ access to the emails of a drug trafficking suspect stored on a Microsoft server in Ireland.
The court had ruled that the Stored Communications Act (SCA) didn't cover searches outside the US, which should instead be handled through an existing mutual legal assistance treaty (MLAT).
However, the court noted in its decision that the rather ancient SCA had been overtaken by technology: "It is overdue for a congressional revision that would continue to protect privacy but would more effectively balance concerns of international comity with law enforcement needs and service provider obligations in the global context in which this case arose," wrote Judge Susan Carney.
Microsoft successfully argued that overturning the ruling would undermine Ireland's sovereignty - as well as severely damaging customer trust.
"It is for just this sort of reason that the government has entered into MLATs with other sovereigns: to address mutual needs for law enforcement while respecting sovereign borders," wrote Carney.
"And it is for just this sort of reason that the government has in other circumstances taken a position, somewhat in tension with the one it takes here, that courts should be particularly solicitous of sovereignty concerns when authorizing data to be collected in the United States but drawn from within the boundaries of a foreign nation."
Of course, not all the judges agreed. "If I can access my emails from my phone, then in an important sense my emails are in my pocket," wrote Judge Dennis Jacobs. "“Extraterritoriality need not be fussed over when the information sought is already within the grasp of a domestic entity served with a warrant."
And Judge Jose Cabranes added that the decision has "indisputably, and severely, restricted an essential investigative tool used thousands of times a year in important criminal investigations around the country."
Microsoft was supported in the case by dozens of technology companies including Amazon, Apple and Mozilla, as well as the Chamber of Commerce - after all, if the July 2016 decision had been overturned, an important precedent would have been set.
Thanks to the overwhelming dominance of US technology companies, internet users all over the world would have found their communications vulnerable to inspection by the US government.
And such a decision could also have paved the way for other countries to follow suit and demand access to customer data held in the US.
Encouraged by the dissenting opinions, the DOJ has indicated that it may appeal to the Supreme Court. However, another likely outcome is a revision of the SCA.
"This decision represents another victory for privacy interests, but as the court makes clear, Congress must step in and update the nation’s email privacy laws for the digital age," says Michael Price, counsel for the Brennan Center’s Liberty and National Security Program.
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