Police departments in Nevada are using a service called Fog Data Science to track cell phone locations without obtaining warrants, purchasing location data that would require court approval if obtained directly from carriers. The practice highlights a growing legal grey area in digital surveillance that the Fourth Amendment wasn't designed to handle.The Fourth Amendment has a data broker-sized loophole. What cops can't get with a warrant, they're buying from companies that harvest your location data. The technology isn't new — your phone constantly pings cell towers and GPS satellites. But the scale and ease of access has fundamentally changed what's possible without judicial oversight.Fog Data Science collects location data from apps and data brokers, then packages it into a searchable database that law enforcement can query. Instead of asking a judge for permission to track a suspect, police departments just log into Fog's system and search for phones that were at specific locations at specific times.The legal theory is that you've already consented to this tracking by agreeing to terms of service for various apps. Never mind that nobody actually reads those terms, or that the concept of "consent" gets murky when the alternative is not using essential services. The data exists, someone is selling it, and the courts haven't definitively said cops can't buy it.This is the Carpenter v. United States decision being quietly circumvented. The Supreme Court ruled in 2018 that police need warrants to get historical location data from cell carriers. So law enforcement found a workaround: buy the data from third parties instead.What makes this particularly insidious is the asymmetry. If you're targeted for surveillance through official channels, there are logs, court orders, opportunities for legal challenge. If police are querying your location through Fog Data, you'll never know. There's no notification, no court filing, no public record.The ACLU and privacy advocates are pushing for legislation to close this loophole, but the tech moves faster than the law. By the time regulations catch up, new surveillance tools will have already emerged. This is the fundamental problem with technology-driven privacy violations: the damage happens before the guardrails get built.Nevada isn't unique here. Police departments across the country are using similar services. The only reason we know about Nevada is because journalists and researchers uncovered the contracts through public records requests. How many other departments are doing this quietly?