Tower dumps are a surveillance method in which law enforcement requests mobile phone records from towers in a specific area over a certain period
A federal judge in Nevada has ruled that the use of “tower dumps” to gather large amounts of cellular data violates the Fourth Amendment, which protects citizens from unreasonable searches and seizures. However, despite this ruling, the evidence collected through such means will still be allowed in court—at least for now.
Tower dumps are a surveillance method in which law enforcement requests mobile phone records from towers in a specific area over a certain period. While investigators might be searching for one suspect’s activity, these dumps often contain the data of thousands of people who happened to be nearby, raising significant privacy concerns.
In her ruling, U.S. District Judge Miranda Du acknowledged that the method infringes on constitutional rights. “The Court finds that the government’s acquisition of the Tower Dump in this case was a search within the meaning of the Fourth Amendment and that search was unreasonable,” she stated. However, she declined to exclude the evidence obtained from the dump, citing the “good faith exception.” According to Du, since this appears to be the first case within the Ninth Circuit to rule on the constitutionality of tower dumps, law enforcement could not have known the practice was illegal at the time. This exception essentially allows evidence to be used if officers were acting in line with existing legal guidance, even if the practice is later deemed unconstitutional.
The case in question involves Cory Spurlock, a Nevada man facing charges linked to a murder-for-hire plot and a conspiracy to distribute marijuana. The tower dump used in his case revealed information about 1,686 mobile users. Investigators say the data was instrumental in building the case against him.
Tower dumps have been used in previous investigations, including a 2010 case involving the so-called High Country Bandits—two individuals who were caught after officers examined a tower dump that contained over 150,000 phone numbers. While the tactic has helped solve crimes, critics argue that it amounts to digital dragnets that sweep up information on people not suspected of any wrongdoing.
This ruling follows a similar decision made in February by a federal judge in Mississippi, who also found tower dumps unconstitutional. That case involved an FBI request for data from nine locations across four different mobile carriers. Unlike in Nevada, the Mississippi court blocked the government from accessing the tower data. The U.S. Department of Justice has since appealed that decision.
As law enforcement continues to rely on digital tools for investigations, courts are beginning to more critically examine the impact of these methods on individual privacy. With differing rulings emerging from various jurisdictions, the legal standing of tower dumps could soon become a matter for higher courts to decide. For now, while the method has been ruled unconstitutional in principle, its use remains a legally grey area—permitted in some circumstances, but increasingly under scrutiny.