Google, Microsoft, Facebook and other tech companies are urging the Supreme Court to rule that digital data is entitled to "strong" protections against searches by the police.

The companies argue in new court papers that the Fourth Amendment, which protects people's privacy, applies to digital data as well as physical material -- although web users necessarily share digital material with a tech platform.

"Users of digital technologies reasonably expect to retain significant privacy in ... data, notwithstanding that technology companies may use or share the data in various ways to provide and improve their services for their customers," the tech companies write. "Fourth Amendment doctrine must adapt to this new reality." Other companies that are signing the brief include Verizon, Dropbox, Airbnb, Mozilla, Snap and Twitter.

In June, the Supreme Court agreed to decide whether law enforcement authorities must obtain a warrant before obtaining cell phone records that reveal individuals' locations over time. The tech companies are not taking a position on that precise question, but say want the court to broadly rule in favor of strong Fourth Amendment protections for digital data.

The underlying criminal case stems from a police investigation of a robbery suspect. In 2011, federal prosecutors obtained court orders requiring Sprint and MetroPCS to turn over 127 days' worth of cell phone location records for Timothy Carpenter, a suspect in robberies in Michigan and Ohio. The prosecutors sought the orders under the Stored Communications Act -- which doesn't require authorities to show they have probable cause to believe the records will yield evidence of a crime.

Some of the records showed that Carpenter was at the locations of the robberies. He was convicted of six robberies and sentenced to almost 116 years.

Carpenter argued that the authorities shouldn't have been able to access the location data without first obtaining a warrant -- which would have required them to convince a judge they had probable cause to think the records would connect Carpenter to the robberies.

The 6th Circuit Court of Appeals sided against Carpenter, ruling that the authorities didn't need a search warrant on the grounds that he lacked a "reasonable expectation of privacy" in records that were held by third parties -- his wireless carriers.

The 6th Circuit's decision drew on a Supreme Court case from 1979, when the court held that the police didn't need a warrant to obtain a list of phone numbers dialed by a suspect. The court ruled in that case that people have no reasonable expectation of privacy in the phone numbers they dial because they have shared that information with their telephone carriers.

That reasoning has been called into question in the digital age. In 2012, the Supreme Court ruled that the police violated a suspect's rights by installing a GPS device on his car without a warrant. In that case, Justice Sonia Sotomayor said in a concurring opinion that people might have an expectation of privacy in certain data -- including Web sites visited, books purchased and email addresses in their contact lists -- even when they share such information with outside companies.

Three years ago, the Supreme Court unanimously ruled that police need to obtain a warrant before searching a suspect's cell phone.

The tech companies now say that the court's interpretation of the Fourth Amendment should "adapt to this new reality" of digital communications.

"The Court should refine the application of certain Fourth Amendment doctrines to ensure that the law realistically engages with Internet-based technologies and with people’s expectations of privacy in their digital data," the companies write. "Consistent with the general reasonable-expectation-of-privacy inquiry, courts should focus on the sensitivity of the data at issue and the circumstances of its transmission to third parties."