A Philadelphia appeals court has ruled that a search warrant is not needed to obtain mobile phone logs during an investigation. The judgment is contrary to the basic rule that warrant which is signed by a judge and based on probable cause is needed during any police investigation.
The details of the ruling are complex but in essence it states that a warrant is not needed because tracking mobile phones “does not require the traditional probable-cause determination” required by the US Constitution’s 4th Amendment – the amendment that prohibits unreasonable search and seizures.
The case came about because a US judge ruled that the Justice Department could not track mobile phone records without warrant. The Justice Department disagreed on the basis that no US residents assume a "reasonable expectation of privacy" with regard to the whereabouts of their mobile phones.
That is to say that mobile phone location tracking does not violate anyone’s privacy because mobile phones (and their users presumably) move about in open and public spaces. This is a concept that the Philadelphia appeals court upheld.
The ruling is interesting for privacy advocates and there is no doubt that the ruling will be tested again. Often laws can’t keep up with the pace of new technology. The issue is whether or not mobile phone ‘movement’ is private. Land line phones records are subjected to warrants because they are often located inside a private house or business so if mobile phones replace land lines – and in many cases they do these days – shouldn’t they be subjected to the same amount of privacy? This is an issue that we need to watch with a close eye for what is ultimately decided in the US may just impact how the UK and the rest of the Europe legally deals with mobile phone privacy.