(CN) - Massachusetts must prove that it had probable cause to get around a search warrant when it looked into a murder suspect's cellphone location information, the state Supreme Court ruled.
Julaine Jules left work one day in August 2004 and was never seen alive again. Her body was found in the Charles River one month later.
Police investigating the crime became aware of a boyfriend of hers, Shabazz Augustine. They obtained copies of telephone call logs betweens Jules and Augustine around the time of her disappearance. Massachusetts later obtained a court order that produced 64 pages of Augustine's cellphone records covering a 14-day period.
Nearly seven years later, a grand jury indicted Augustine for Jules' murder. Pointing out that police never obtained a search warrant, Augustine moved to suppress the cell site location information (CSLI) under the Fourth Amendment.
A Superior Court judge in Suffolk County court agreed, stating that "there was a search such that this information must be suppressed."
On appeal, the commonwealth argued that Augustine did not have an expectation of privacy in the phone records and that the records should not be excluded even their acquisition was considered an official search.
Though the Massachusetts Supreme Court agreed that Augustine had a reasonable expectation of privacy in the CLSI at issue, a five-justice majority vacated the suppression order Tuesday.
On remand, the lower court must decide whether an affidavit that Massachusetts submitted in support of its application for the cellphone records "demonstrated probable cause."
As people today carry cellphones "almost permanent attachments to their bodies," cellular records can be used to track a person's location, Justice Margot Botsford wrote for the majority.
"There is a strong argument that CSLI raises even greater privacy concerns than a GPS tracking device," she added.
Thus the state's acquisition of the cellphone data over a two-week span was an instance of tracking Augustine's movements, according to the ruling.
"In the present case, the defendant made a showing of a subjective privacy interest in his location information reflected in the CSLI records, and for all of the reasons we have considered here, we concluded that this interest is one that our society is prepared to recognize as reasonable," Botsford wrote.
Justice Ralph Gants wrote in dissent that the majority exaggerated the reliance Americans today have on their cellphones.
"If we take the annual volume of voice minutes (2.3 trillion), and divide it by the multiple of the total United States population in July, 2012 (313.87 million), and the number of minutes in a year (525,600), we learn that cellular telephone users spoke on the telephone in 2012 only 1.4 per cent of the day," Gants wrote, joined by Justice Robert Cordy. (Parentheses in original.)
Survey data backs up these findings, he noted.
"Therefore, while it may seem as if Americans are always talking on their cellular telephones, they are actually doing so less than two per cent of the day," Gants wrote (emphasis in original). "Therefore, there is a world of difference between telephone CSLI and registration CSLI in terms of the location points they will reveal and the degree to which they will intrude on personal privacy."
Requiring a search warrant puts the bar too high, the dissenting justices said.
"Because of the probable cause requirement and, more importantly, because there must be probable cause that the CSLI will produce evidence implicating the telephone user in a crime, the police will not be able to obtain a search warrant unless they already have obtained significant other information implicating the telephone user in a crime," Gants wrote.
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