LANSING, Mich. (Michigan News Source) — Attorney General Dana Nessel is dialing up the pressure on telecom companies accused of giving scam callers a free pass.

Nessel announced the launch of Operation Robocall Roundup on August 7, a multistate campaign with 50 other attorneys general to force telephone service providers to block illegal robocalls. Thirty-seven companies received warning letters, ordering them to either follow federal rules or risk losing access to the nation’s phone networks. 

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“I look forward to continuing to work with the Anti-Robocall Litigation Task Force to protect people from these persistent and intrusive calls,” Nessel said in a statement.

According to Nessel’s office, the companies ignored basic Federal Communications Commission (FCC) requirements: responding to traceback requests from authorities, registering in the FCC’s Robocall Mitigation Database, or filing a plan to show how they’ll cut off scam traffic. 

By skipping those steps, her office said, they are letting robocallers slip into their networks and onto the phones of Michigan residents.

More than 100 downstream providers that accept traffic from the flagged companies will also get letters, warning them that they’re working with carriers unwilling to play by the same rules as everyone else.

The FCC has already begun booting noncompliant providers. This week, it removed seven from the Robocall Mitigation Database, cutting off their ability to pass calls through other carriers.