Legislation that would require law enforcement to obtain a search warrant before asking technology companies to hand over dated emails unanimously moved forward in the U.S. House of Representatives on Wednesday, although its prospects for becoming law this year remain uncertain.

The House Judiciary Committee voted 28-0 to approve the Email Privacy Act, which would update a decades-old law to mandate federal authorities get a warrant to access emails or other digital communications that are more than 180 days old.

Currently, law enforcement and civil agencies can ask a service provider to turn over private communications of that age with only a subpoena, which is subject to less judicial oversight than a warrant.

Prior to Wednesday’s vote the bill had gained sponsorship from 315 of a possible 435 House lawmakers, making it the most supported bill in the chamber to not earn a vote.

More than a quarter of the Senate has endorsed similar legislation, including John Cornyn, the No. 2 Republican in the chamber, and it is widely supported by the technology industry and privacy advocates.

The White House also has said it favors reforming the 1986 Electronic Communications Privacy Act, but it has not endorsed specific legislation.

Despite its strong support, it is unclear if the Email Privacy Act will become law in a gridlocked Congress unlikely to tackle much significant legislation during an election year.

A package of minor amendments from Rep. Bob Goodlatte, the Republican chairman of the committee, was adopted Wednesday, including the removal of a requirement to serve warrants to the subject of an investigation. The bill requires a warrant to be given only to the email provider.

That change and others prompted ire from a coalition of more than 50 civil liberties groups, trade associations and technology companies, including Amazon, Microsoft and Facebook. While maintaining their support, the coalition said in a letter to the committee that the bill "does not achieve all of the reforms we had hoped for."

Disagreements over whether civil agencies such as the Securities and Exchange Commission should be allowed to rely on subpoenas continually slowed the bill, which has floated around Congress for several years.

SEC Chairwoman Mary Jo White has argued that because her agency lacks the power extended to law enforcement to use warrants, it should be granted an exception to continue using subpoenas for financial fraud investigations. Such a move was ultimately rejected.