A federal judge in Nevada has ruled that “tower dumps,” the practice of police collecting data from all mobile phones connected to specific cell towers during a defined period, violate the Fourth Amendment of the U.S. Constitution, which protects against unreasonable searches.
Cell towers routinely log the presence of nearby mobile devices, typically every seven seconds. When authorities conduct a tower dump, they compel telecommunications providers to hand over phone numbers and identifying information for all devices connected to a designated tower within a particular timeframe. This means data can be collected from subscribers of any carrier, such as AT&T, Verizon, or T-Mobile. In populated areas, such a data sweep can encompass information from tens of thousands of individuals.
Law enforcement agencies have utilized tower dumps in criminal investigations. However, the practice has faced criticism due to its extensive reach, as it gathers data from everyone in a given vicinity rather than targeting specific suspects, raising significant concerns under the Fourth Amendment’s protection against unreasonable searches and seizures.
This specific ruling originated from the case of Cory Spurlock, a Nevada resident accused of marijuana distribution and involvement in a murder-for-hire plot. Investigators employed a tower dump to place Spurlock’s cellphone near several crime scenes. Spurlock’s legal team challenged this method, arguing it was an unconstitutional search and that any evidence obtained should be suppressed. While police had secured a warrant, they initially contended the data collection was not a search under the Constitution.
Judge Miranda M. Du of the U.S. District Court for Nevada determined that tower dumps do indeed qualify as searches. She further ruled that the warrant used in Spurlock’s case functioned as a general warrant, which is explicitly prohibited by the Fourth Amendment.
Despite finding the search unconstitutional, Judge Du allowed the evidence gathered in this instance to be admitted. She applied the good faith exception, reasoning that the officers believed they were acting lawfully at the time, as no court in the Ninth Circuit had previously ruled on the constitutionality of tower dumps.
This decision marks the first occasion a court within the Ninth Circuit has addressed the constitutionality of tower dumps. Other courts have begun to examine the issue; in February, a federal judge in Mississippi issued a similar ruling, which the Department of Justice has since appealed.




