Hugh Pickens writes "The NY Times reports that the case of Mikhail Mallayev, who was convicted in March of murder after data from his cellphone disproved his alibi, highlights the surge in law enforcement's use of increasingly sophisticated cellular tracking techniques to keep tabs on suspects before they are arrested and build criminal cases against them by mapping their past movements. But cellphone tracking is raising concerns about civil liberties in a debate that pits public safety against privacy rights. Investigators seeking warrants must provide a judge with probable cause that a crime has been committed, but investigators often obtain cell-tracking records under lower standards of judicial review — through subpoenas, which are granted routinely, or through an intermediate type of court order based on an argument that the information requested would be relevant to an investigation. 'Cell phone providers store an increasing amount of sensitive data about where you are and when, based on which cell towers your phone uses when making a call. Until now, the government has routinely seized these records without search warrants,' said EFF Senior Staff Attorney Kevin Bankston. Last year the Federal District Court in Pittsburgh ruled that a search warrant is required even for historical phone location records, but the Justice Department has appealed the ruling. 'The cost of carrying a cellphone should not include the loss of one's personal privacy,' said Catherine Crump, a lawyer for the ACLU."