In a precedent-setting decision, a federal appellate court this week ruled that judges have the option of asking prosecutors to obtain a warrant before they are allowed to access to an person's cell phone location data.
But the court left untouched the question of whether access to such data is protected under Fourth Amendment rights against unreasonable search and seizure.
The ruling by the U.S. Court of Appeals for the Third Circuit rejected government claims that current statutes require courts to always allow access to cell phone data whenever prosecutors are able to show they have "reasonable cause" for wanting it. (A copy of the verdict is available for download from the Electronic Frontier Foundation's Web site.)
In its ruling, a three-judge panel for the Third Circuit noted that the language of the Stored Communications Act (SCA) gives judges the option of asking prosecutors to obtain a warrant, based on probable cause, in some situations.
"We are unwilling to remove that option although it is an option to be used sparingly," U.S. Circuit Judge Dolores Sloviter wrote in a 32-page opinion.
This is the first time that a federal appeals court has ruled on the legal standards that law enforcement needs to meet when seeking access to cell phone records.
The decision is tied to a 2008 request by prosecutors in Pittsburgh for cell phone location data in connection with a narcotics investigation. The request, filed under the SCA, sought a court order requiring a cellular service provider to disclose the "transactional records" of a suspected drug trafficker.
Prosecutors wanted the service provider to include historical cellular tower data, cellular tower site information and other tracking data because they claimed there were reasonable grounds to believe the information would be relevant to its ongoing investigation.
However, Pittsburgh's magistrate judge to whom the request was made denied the government's request, and held that cell phone tracking data was protected under the Fourth Amendment.
In her ruling magistrate judge Lisa Lenihan held that cell phone information was "extraordinarily" private and sensitive and any government demands for access to that data had to be based on probable cause grounds and not mere reasonable cause.
Judge Lenihan's verdict was signed by four other judges and later upheld by a District Court judge as well.
In appealing the decision, the government argued that the SCA allowed it the authority to ask for the data without requiring a warrant for it. The government also contended that no Fourth Amendment rights were being violated by its demands for the data.
In its ruling this week, the appeals court noted that the SCA contains no explicit requirement for the government to obtain a probable cause warrant in seeking cell phone data. However, the way the statute is worded gives judges the option of asking for a warrant if they think it is justified, the judges noted.
"There is an inherent contradiction in the statute or at least an underlying omission," in the statute that would appear to give judges that discretion, Judge Sloviter wrote.
However, any exercise of that discretion would need to be based on a finding that a warrant is absolutely needed to protect an individual's rights against unreasonable search, the court noted.
In arriving at its decision, the appellate court also noted that Judge Lenihan's earlier decision cannot be allowed to stand because it does not offer any explanation as to why a warrant is required in this specific case.
The type of cell phone data being sought by the government is covered by the SCA, and the government is within its authority to ask for the data, the appellate court noted.
For Judge Lenihan to refuse the government's request, a determination needs to be made on why reasonable-cause standards are not sufficient in this current case, or if there is reason to believe that such an order would violate Fourth Amendment rights.
Kevin Bankston, an attorney with the Electronic Frontier Foundation, an advocacy group that had filed an amicus brief in the case, welcomed the verdict.
"The SCA allows the government to obtain cell location data without a warrant. This ruling holds that under the statutes, courts have the discretion to instead require the government to show probable cause and get a warrant [when needed,]" Bankston said.
"This decision gives the front-line judges new tools to exercise oversight and to raise the bar when the government seeks cell phone location data," he said.
Jaikumar Vijayan covers data security and privacy issues, financial services security and e-voting for Computerworld. Follow Jaikumar on Twitter at @jaivijayan or subscribe to Jaikumar's RSS feed . His e-mail address is firstname.lastname@example.org.