In January 2014, the FBI secretly entered Gartenlaub's home while he and his wife were on vacation in China. Agents scoured the home, taking pictures, searching through boxes and books, and—critically—making wholesale copies of Gartenlaub's hard drives.

Agents were authorized by the secret Foreign Intelligence Surveillance Court ("FISC") to search for evidence that Gartenlaub was spying for the Chinese government. There’s only one problem with that theory: the government never produced any evidence to support it. But the FBI’s months-long forensic search of his hard drives turned up evidence of another crime—roughly 100 files containing child pornography, buried among thousands of other files, saved on an external hard drive.

He was tried and convicted for possessing child pornography, and appealed his conviction to the Ninth Circuit Court of Appeals. EFF and ACLU filed an amicus in support of his appeal. Our brief  argued that the FBI’s search of Gartenlaub’s hard drives for evidence of regular, domestic crimes violated the Fourth Amendment, and we urged the Court to adopt a rule that would prohibit the FBI from using evidence that it obtained that was outside the scope of the initial search authorization.

The Ninth Circuit upheld Gartenlaub's conviction in an unpublished memorandum disposition in October 2018. Although the court said that the search of his computers  came "perilously close to the exact abuses against which the Fourth Amendment was designed to protect," it nevertheless found that the district court did not commit clear error in holding otherwise.