It's no secret that app data can reach investigators without much oversight, but you might be surprised at just who is buying that data. The Intercept and advocacy group Tech Inquiry have learned that the US Treasury Department recently bought sensitive app data from Babel Street, the same firm that handed info to the Secret Service and other agencies. The department spent over $300,000 on two contracts in the past four months to collect data for the sake of investigations.

One contract, made official in July 2021, gave Office of Foreign Assets Control (OFAC) investigators access to mobile app location data from Babel Street's Locate X tool. The info will help OFAC target people and enforce international sanctions, according to the contract. As you might expect, there's a concern the office is effectively circumventing Fourth Amendment search restrictions. The data is technically anonymous, but it's relatively easy for an investigator to link data to individuals.

The other contract, from September 2021, gives the Internal Revenue Service a tool that scrapes information from "public digital media records." The software will theoretically help the IRS catch tax evaders through online activity like social media posts and forum conversations. While it's legal to view that content, the Treasury wants Babel Street to provide "available bio-metric [sic] data" like addresses and marital status that may create a detailed profile.

The concern isn't just that the Treasury might be circumventing the Fourth Amendment by obtaining some data (particularly locations) without a warrant. This also represents an expansion of "invasive surveillance," Tech Inquiry founder Jack Poulson told The Intercept. Rather than scaling back its efforts, the US government is stepping things up.

We've asked the Treasury for comment. There's no guarantee it will back off. With that said, Senator Ron Wyden and others are pushing legislation that would require a court order for these data purchases. If bills like The Fourth Amendment Is Not For Sale Act ever become law, the government would at least need to pass a basic legal test to buy this sensitive material — even if officials wouldn't require your knowledge.