Ever heard of a “stingray”? You’re probably envisioning a flat tropical fish, but that’s not the only kind of dangerous stingray out there. The other is a little known tracking device that can locate your cell phone with extraordinary precision. The ACLU has filed an amicus brief in what will be the first case in the country to address the constitutional implications of these scary new devices, and we’ll be following it closely in the months to come.

What’s particularly disturbing about a stingray is how indiscriminate it is. Not only does it track the target of an investigation, but it also collects information about the devices and whereabouts of third parties, bringing about serious questions on whether they can ever be used consistent with the Fourth Amendment.

In this pilot case the issue is not whether using stingrays amounts to a “search” – the government acknowledges that it does – but rather the degree to which police must explain the technology they are using when getting a warrant. In this instance, the papers the government submitted to get the so-called “warrant” never told the judge that the government wanted to use a stingray, what the device is, or how it works. In doing so they left out essential information – including the fact that stingrays collect information about third parties, that they can pinpoint targets even within their homes, and that some models capture content, not just location.

The stingray is not the first piece of modern technology to challenge the Fourth Amendment in a new way, and it surely won’t be the last. Some judges are pushing back and denying broad surveillance requests when the government fails to explain the technology. Hopefully more will follow suit, because judges are not rubber stamps and they can’t act as constitutional safeguards of our privacy when the government isn't honest about how they're conducting searches.