Behind closed doors today, the Supreme Court will consider taking up two cases concerning whether police, after seizing a cellphone during a lawful arrest, can search the phone's data without a warrant.

Lower courts have divided on the issue. Those courts upholding the warrantless searches have relied at times on a 1973 Supreme Court precedent that privacy advocates say doesn't contemplate modern-day technology.

In that case - United States v. Robinson - a man was arrested for driving with a revoked license. While police officers conducted a pat-down, they found a cigarette package filled with heroin. The court upheld the warrantless search, explaining that police can conduct a full search of a person incident to a lawful arrest.

But privacy advocates say things have changed since that case was decided.

"The search of a cellphone incident to arrest is far beyond the limited type of search the Supreme Court authorized in Robinson," says Hanni M. Fakhoury, an attorney with the Electronic Frontier Foundation.

Indeed, in May, a majority of the U.S. Court of Appeals for the First Circuit wrote that years ago the Supreme Court" could not have envisioned a world in which the vast majority of arrestees would be carrying on their person an item containing not physical evidence but a vast store of intangible data-data that is not immediately destructible and poses no threat to the arresting officers." The appeals court said that allowing a search of the data without a warrant would create a serious and recurring threat to the privacy of countless individuals.

During their private conference the justices will consider two cases with slightly different circumstances.

One case involves Brima Wurie, a Boston man linked to a 2007 drug sale in the parking lot of the Lil Peach convenience store.

At the police station, police officers noticed that Wurie's Verizon LG phone (a flip phone that is considered old technology by today's standards) kept receiving a call from a number identified as "my house" on the external caller ID screen on the front of the phone. The officers opened the phone and accessed its call log. They took the number and ran it through a reverse directory to obtain an associated address. Officers went to the house and eventually, with a warrant, found 215 grams of crack cocaine. Wurie was later sentenced to 262 months in prison.

Wurie appealed his conviction, arguing that the evidence obtained as a result of the warrantless search of his cellphone should have been suppressed. The government argued that the search of the cellphone was necessary in part because Wurie or others might try to remotely wipe the contents of the phone.

The appellate court ruled in Wurie's favor.

It said that police can prevent the wiping by turning the phone off, removing its battery, placing it in a special bag that blocks it from receiving signals, or copying its contents without accessing them.

The other case involves a much more sophisticated phone - a Samsung smart phone - capable of accessing the internet, capturing photos and videos and storing voice and text messages, among other functions. The search was much more extensive than in the Wurie case.

In 2009, David Leon Riley was stopped by police for driving a car with expired tags. When police learned he was driving with a suspended license, they impounded the car. While conducting an inventory search of the vehicle , the officers discovered concealed and loaded weapons. They arrested Riley and seized his cellphone.

A warrantless search of the smart phone yielded videos and photographs showing Riley's affiliation with a gang, and linked him to a recent gang shooting. Riley was convicted for his role in the shooting and received an enhanced sentence because of his gang affiliation. He argued that the search of his cellphone violated the Fourth Amendment's ban on unreasonable search and seizure because it was performed without a warrant and there were no exigent circumstances to justify the search.

The California Court of Appeal affirmed his conviction, and the California Supreme Court declined to take up the case. In his appeal to the U.S. Supreme Court, Riley's lawyers argue that "cellphones are capable of storing a virtually limitless amount of information in a single, compact device." They call the phone a "mini, yet powerful, computer that happens to include a phone."

They write, "the Fourth Amendment should require the detached scrutiny of a neutral magistrate before allowing the police to rummage through the digital contents of such a device."

According to the Pew Research Center, 56% of American adults now own smartphones. The phones send emails, store text conversations , create a roadmap of an individual's schedule and also store financial information.

We could learn as early as Friday whether the Court will hear one or both cases.