Here’s the answer in depth:
https://www.lawfaremedia.org/article/when-the-government-buy...
I find it interesting where the line between freedom and acceptable government intervention seems to be for many people. There must be an aspect of “what do I have to worry about” that doesn’t kick in until people explicitly see what they have to worry about looming.
"The standard argument in favor of unfettered government purchases of private data is that such data is commercially available, and so anyone should be able to purchase it, including government officers."
Agreed.
"... while government officials can generally purchase items available to the public without constitutional restriction, sensitive private data about cell phone users isn’t actually available to the public."
What? I may be misunderstanding, but this looks like a deliberate attempt to conflate two concerns: publicly available data for sale and sensitive private data. I don't see any argument here against the government buying publicly available data.
Because it’s “on the market” it’s deemed “public”, but that market only is open to governments.
Similar to how one cannot sign away one’s constitutional rights in a contract.
Regardless, if people cannot have privacy because companies can coerce and buy so much information about them, then that too is a violation that should be illegal. (For example because it's increasingly impractical to live without a smart phone and cell tower connections, or avoid iTags.)
> The third-party doctrine is a United States legal doctrine that holds that people who voluntarily give information to third parties—such as banks, phone companies, internet service providers (ISPs), and e-mail servers—have "no reasonable expectation of privacy" in that information. A lack of privacy protection allows the United States government to obtain information from third parties without a legal warrant and without otherwise complying with the Fourth Amendment prohibition against search and seizure without probable cause and a judicial search warrant.
The fourth amendment is a restriction on the government's ability to search or seize - things that a regular private entity is not permitted to do at all, that represent an enormously abusable power. I don't see how buying public information fits into that.
> if people cannot have privacy because companies can coerce and buy so much information about them, then that too is a violation that should be illegal.
Perhaps. But looking to ban the government from buying that information on the open market is putting the cart before the horse. If the problem is our private information being sold, let's look for a fix for that that would protect us from large companies or wealthy individuals with a grudge, rather than focusing narrowly on the government.