Washington (CNN) The federal agency charged with policing violations of campaign finance laws just lost its power to enforce those laws as the country heads into the 2020 elections.

The Federal Election Commission will have just three members following the departure of Matthew Petersen, who announced on Monday that he will resign his commission post August 31 . Federal law requires four or more commissioners to approve new rules or take actions to punish those who violate election law.

The six-member commission has not operated at full strength for some time , and it has often deadlocked along partisan lines on important issues, such as donor disclosure.

The agency was already "dysfunctional," Rick Hasen, an election law expert at the University of California at Irvine, wrote on Twitter. "But given the threat of foreign intervention in the 2020 elections, the inability of the FEC to act on an emergency basis is BAD NEWS."

Tiffany Muller, the president of pro-regulation End Citizens United Action Fund, said a weakened FEC "is a recipe for a corrupt government further beholden to big donors and special interests."

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