The Supreme Court heard arguments Tuesday in a huge privacy case that will determine whether the cops can search the digital contents of your cellphone without a warrant. The case involves a San Diego college student (and alleged gang member) named David Riley, who was pulled over in 2009 for having expired tags. Police seized Riley’s Samsung Instinct M800 and used a photo on it to charge him with participating in a drive-by shooting. He was ultimately convicted and sentenced to 15 years to life. During arguments on Tuesday morning, Riley’s lawyer Jeffrey Fisher told the justices there are “very, very profound problems with searching a smartphone without a warrant.” He’s arguing for his client that such searches violate the Fourth Amendment, which protects against unreasonable searches and seizures. More