> If it shouldn't be legal for law enforcement to get that data without a warrant, why the hell is it legal for the data brokers to buy and sell it?

Good question. If it's freely available why is LE the only ones being restricted? I'd much rather they had it than the insurance and advertising industries.

I don't disagree with your sentiment.

However, the reason it's legal is that we often give away permission to do so without even knowing it. For example, the slashdot terms of service include:

"By sending, uploading, displaying, posting or transmitting Content to any area of the Sites, you grant us and our subsidiaries, affiliates, agents, employees and designees a worldwide, non-exclusive, sub-licensable (through multiple tiers), assignable, royalty-free, perpetual, irrevocable right to link to, reproduce, distribute (through multiple tiers), adapt, create derivative works of, publicly perform, publicly display, digitally perform or otherwise use such Content in any media or site now known or hereafter developed. You further hereby grant Company permission to display your logo, trademarks and company name on the Sites and in press and other public releases or filings. Further, by submitting Content to the Company, you acknowledge that you have the authority to grant such rights to the Company."

and:

"Slashdot Media may assign, transfer or sub-license this Agreement without your consent and without notice to you."

The problem is that these terms are often buried in a big legal agreement which itself is buried on a website or something you click through without thinking.

Whether this should be legal or not is one of those things that I'd have a fairly easy time arguing either side of. On one side, part of the bargain you make to use a site like slashdot for free is to see advertisements and have your data scraped. On the other side, I don't think many of us really want our cell companies selling our geolocation data. The question is where should the line be drawn and what should or should not be legal.

Note that in the US we generally have laws that prohibit this type of thing for medical records (HIPAA) but for non-medical records there are few if any protections. I'd argue that there needs to be more protection. I also realize that in order to not have to pay (or in order to pay less) for certain services that those services being able to sell certain datasets derived from my usage of those services is required.

Because when you signed up for whatever thing you signed up for, you agreed to let them sell your data.

You could outlaw that practice, but you'll have to figure out how to unwind hundreds of millions of contracts equitably. Also, if Montana did this unilaterally, I'm guessing the easiest solution for most companies would to simply stop doing business in Montana, as it's not a huge market.

I agree - make it illegal to sell personal data instead.

Good point.

Of course, our tech overlords have bought and paid for all the politicians so nobody will stand up to them.

Better watch out, the GQP might get mad you didn't call it GULF OF 'MURICA! and send some "agents" wearing facemasks and no ID to black bag you without an arrest warrant. After that they'll ship you to Egypt or El Salvador without so much as a hearing.

Well if DJT gets his way, it won't matter even if you are an American citizen.