The United States Internal Revenue Service says it purchased access to a marketing database that offers location data for millions of US cellphones, so the IRS can identify and track persons suspected of tax-related crimes.

The unsuccessful effort illustrates how marketing data, and locatin data, are used by law enforcement to track and I.D. individual people suspected of criminal activity.

Reports Byron Tau at the Wall Street Journal:

The IRS Criminal Investigation unit, or IRS CI, had a subscription to access the data in 2017 and 2018, and the way it used the data was revealed last week in a briefing by IRS CI officials to Sen. Ron Wyden’s (D., Ore.) office. The briefing was described to The Wall Street Journal by an aide to the senator.

IRS CI officials told Mr. Wyden’s office that their lawyers had given verbal approval for the use of the database, which is sold by a Virginia-based government contractor called Venntel Inc. Venntel obtains anonymized location data from the marketing industry and resells it to governments. IRS CI added that it let its Venntel subscription lapse after it failed to locate any targets of interest during the year it paid for the service, according to Mr. Wyden’s aide.

Justin Cole, a spokesman for IRS CI, said it entered into a “limited contract with Venntel to test their services against the law enforcement requirements of our agency.” IRS CI pursues the most serious and flagrant violations of tax law, and it said it used the Venntel database in “significant money-laundering, cyber, drug and organized-crime cases.”

Senator Ron Wyden responded:

And some Fourth Amendment constitutional questions.

IRS Used Cellphone Location Data to Try to Find Suspects