Data brokers harvest location information from our phone apps, then sell access to the highest bidder, including government. This is a way sheriffs and bounty hunters in anti-abortion states may try to identify and punish people seeking and providing abortion.

Some good news: three members of Congress are investigating this problem, and have sent letters to five location data brokers. The legislators are Rep. Maloney, chair of the House Oversight Committee; Rep. Krishnamoorthi, chair of the Consumer Policy Subcommittee; and Rep. Jacobs, author of the “My Body, My Data” bill. Four of these location data brokers (Babel Street, Digital Envoy, Gravy Analytics, and Safegraph) are discussed in EFF’s recent deep dive on federal government purchases of phone app location data. The fifth broker is

The letters begin by quoting EFF’s Eva Galperin regarding the “unprecedented digital surveillance” faced today by abortion seekers. They also cite EFF’s reporting on how the State of Illinois bought data from Safegraph. Most importantly, the letters ask the location brokers for information, including a list of the phone apps the companies use to gather location data, a list of the business partners from which they obtain this data, and a list of purchasers of location data related to family planning clinics.

The three representatives also sent letters to the makers of five period tracking apps. They ask for information about their data collection and dissemination, and express concern about “the potential misuse of this sensitive, private data to invade the privacy of those seeking reproductive health care.”

Sunshine is the best disinfectant. Next comes legislation. Congress must enact a comprehensive consumer data privacy law, to dry up the silos of location data that private companies have gathered about us. Congress must also enact Rep. Jacobs’ “My Body, My Data” bill; you can help pass it by taking action here.