With a deadline for public comment quickly approaching, critics are charging that regulators on the Federal Communications Commission are trying to suppress debate in a rush to impose new privacy rules on broadband providers.

“Comments are the public’s one opportunity to influence the actions of a powerful, but unelected and, largely, unaccountable agency,” a coalition of 30 groups said in a letter delivered to the agency late on Friday. “When that opportunity is stifled or restricted, steps must be taken to ensure that voices of Americans are sufficiently heard in the context of FCC proceedings.”