The legislation would require that phone carriers implement call authentication technology without an additional charge for consumers.

The bill also would allow carriers to offer call blocking services to consumers on an "opt-out" basis and would attempt to ensure that important calls are not blocked.

However, credit union trade groups said that essential calls could be blocked under the legislation.

CUNA President/CEO Jim Nussle said that a recent Federal Communications Commission plan would include a complaint and notice mechanism for opt-out and opt-in call-blocking systems. The House legislation would require that process only for opt-out calls.

"As a result, credit unions would have no notice of when a consumer has chosen to opt-in to no longer receiving their calls due to their decision to limit their telephone services to 'white list' contacts exclusively," he wrote in a letter to House committee leaders.

He added that the legislation would not allow callers to seek recourse from the FCC for erroneously blocked calls.

NAFCU agreed that the legislation could block phone calls from a member's credit union.

Any legislation should recognize the difference between illegal robocalls, and legitimate calls made using an automatic telephone dialing system, Brad Thaler, NAFCU's vice president of legislative affairs said, in a letter to the committee.

"The bill's narrow safe harbor provision could also expose credit unions to liability even if they have checked the reassigned numbers database," he said.

However, a consumer group applauded the committee's bill.

"This bipartisan bill is an important step forward in the fight to stop unwanted and illegal robocalls," said National Consumer Law Center Senior Counsel Margot Saunders.