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The "Microsoft Ireland" Case (Amicus Brief) [Update]

The Brennan Center' filed an amicus brief cautioning the Second Circuit against repeating a lower court's errors in reasoning concerning Fourth Amendment protections for digital data.

Published: January 24, 2016

The central issue in this case is whether a domestic search warrant can compel American companies to produce data stored in servers outside the United States.

The “Microsoft Ireland” case began in December 2013 when a district court judge in New York issued a warrant asking Microsoft to produce all emails and other private information associated with a certain account. Most of that data is in Ireland, however, stored in one of the many datacenters Microsoft maintains around to improve the speed of its network for foreign users. Microsoft produced basic account information kept on its servers in the United States, but refused to turn over any data stored on servers in Ireland, arguing the government’s warrant does not apply extraterritorially. In response, the district court held Microsoft in contempt.  

Microsoft appealed to the Second Circuit and won in July 2016. The Brennan Center, in conjunction with the Constitution Project, the Electronic Frontier Foundation, the American Civil Liberties Union, and O'Melveny & Myers LLP as pro bono counsel, filed an amicus brief in support of Microsoft.

The government petitioned the Court to rehear the case, but was denied en banc in January 2017. Judge Carney presented the Court’s rationale in a concurring opinion.

In October 2017, the government successfully petitioned the Supreme Court to review the case. Once again, the Brennan Center, in conjunction with the American Civil Liberties Union, Electronic Frontier Foundation, R Street Institute, and Restore the Fourth filed an amicus brief, warning the Court to avoid critical errors in the government’s reasoning, which could dramatically curtail Fourth Amendment rights for American’s electronic data.

First, the brief argues that the Fourth Amendment “moment” where digital data is protected, takes place at the point of seizure regardless of when a law enforcement officer views it and requires a warrant. The brief takes issue with the government’s claim that because Microsoft has the legal ability to migrate data between the U.S. and Ireland, it is not a search or seizure for the company to do so at the government’s demand. Second, amici urge the Court to make clear that a subpoena is not constitutionally sufficient to compel a service provider to disclose emails stored on behalf of a user—no matter where the emails are stored. Finally, amici maintain that accepting the government’s position would threaten the privacy interests of people residing in the United States, encouraging foreign governments to demand data belonging to U.S. persons under standards far less protective than those applicable in this country.

As increasing amounts of personal data are stored digitally, questions of Fourth Amendment protections for digital data will become even more critical in assuring the future of digital privacy. The Brennan Center is therefore urging the Supreme Court to carefully evaluate the implications of relying on the government’s reasoning as it considers this case.

Read the Supreme Court Amicus Brief [PDF]

Read the Second Circuit’s Order [PDF]

Read Judge Carney’s Concurrence [PDF]

Read the Second Circuit Amicus Brief [PDF]

Microsoft's Brief to the Court of Appeals for the Second Circuit

The Warrant