On September 24, 2026, the Fourth Circuit held that Baltimore police conducted a Fourth Amendment search when they used a cell-site simulator to locate a man’s phone. The court did not decide whether the pen register order the police had obtained satisfied the warrant requirement, and it affirmed judgment for the detectives and for the police department. The opinion, Andrews v. Baltimore City Police Department, is a close look at the gap between a constitutional rule and a remedy.
What happened
A cell-site simulator acts like a cell tower, prompting nearby phones to send identifying signals so that police can locate a phone in real time, more precisely than with historical cell-site records. While connected to the device, a phone could not receive calls or texts. In Baltimore, officers walked the blocks until the simulator pinpointed Kerron Andrews’s phone to a specific townhome. Detectives entered with consent and found Andrews. The Maryland courts suppressed the evidence in his criminal case. Andrews then sued for damages.
Why it was a search
Writing for the panel, Judge Nicole Berner relied on Carpenter v. United States and the Supreme Court’s 2026 decision in Chatrie v. United States, which held that police “invade a cell-phone user’s reasonable expectation of privacy when they access his Location History.” She stressed the special protection of the home and called the technology “akin to sense-enhancing technology” that lets the government see into a home. The court also noted that police gathered the location information directly rather than from a third party, which set the case apart from Carpenter, where the records came from a phone company. The court held that using the cell-site simulator constituted a search under the Fourth Amendment. It did not decide whether the pen register order satisfied the warrant requirement, because the detectives were entitled to qualified immunity.
Why the police still won
Qualified immunity protects officers from damages unless they violated a right that was clearly established when they acted. The court found that no federal appellate court had squarely addressed the real-time use of a simulator, and the Supreme Court had not either. Both Carpenter and Chatrie were decided after the police used the device. The detectives were therefore entitled to qualified immunity on the federal claims, and to public official immunity on the Maryland constitutional claims, which required gross negligence or malice.
The department’s liability failed for a different reason. To hold a city agency liable, a plaintiff generally has to show an unconstitutional policy or custom. Andrews pointed to an FBI non-disclosure agreement but, after three years of discovery, no other evidence of one. Even so, the court did not leave that agreement alone. It warned that law enforcement may not use a private non-disclosure agreement to conceal information when seeking warrants or in court.
Two different remedies, two different results
The case shows that a violation can lead to more than one kind of remedy. In Andrews’s criminal case, the remedy was suppression of the evidence, and the Maryland courts ordered it. In his civil suit, the remedy would have been damages, and that is where the immunity doctrines stood in the way. The same conduct produced a win in one courtroom and a loss in the other, and neither result contradicts the other.
What the opinion does not say
Two limits are worth keeping in mind. First, because the court did not decide whether the pen register order met the warrant requirement, the opinion is not a finding that the police broke the law in every respect. Second, Judge Quattlebaum concurred in part and in the judgment. He would not have reached whether using the simulator is a search, noting that the defendants had conceded the point below, and he questioned how closely Carpenter and Chatrie compare. The ruling is one appellate panel’s decision.
What the case shows about rights and remedies
Looking at this question, I found Kenneth Carnesi, Sr.’s book, The Bill of Rights At A Crossroads, instructive. Carnesi discusses how technology can move faster than the law, and he gives attention to the limits of remedies, which show how much a right is worth in daily life. The book also examines Carpenter and digital surveillance. Andrews fits that discussion closely: the police used the technology before the Supreme Court decided Carpenter or Chatrie, and the Fourth Circuit concluded that the right was therefore not clearly established when the detectives acted.
For readers, the lesson is not that the Fourth Amendment failed. It is that recognizing a right, enforcing it, and compensating a violation are three different questions, and courts answer them one at a time.
Kenneth Carnesi, Sr. is COO of Anaptyx MSP and founder of the Anaptyx CivicConnect™ dedicated BEAD Program team. He is the author of BEAD: Unlocking the Future and The Bill of Rights At A Crossroads.