A coalition of 112 organizations is urging House and Senate negotiators to move quickly to resolve differences over legislation that would strengthen the protections afforded federal employees who blow the whistle on waste, fraud and abuse.

The House approved a bill, 331 to 94, to broaden whistle-blower rights 15 months ago, and the Senate approved its version on a voice vote in December. But the bills contain different provisions, and advocates for whistle-blowers are concerned that election-year campaigns may cut short the time that Congress has to get a compromise version to the White House.

“We offer our support to expeditiously conclude the process of reconciling House and Senate passed versions of this vital good government legislation,” the coalition said in a letter sent Wednesday to members of the House and Senate who will put together a final bill.

Some groups in the coalition have worked on expanded whistle-blower protections for eight years. They contend that the Merit Systems Protection Board and the U.S. Court of Appeals for the Federal Circuit have wrongfully interpreted or taken a too narrow view of whistle-blower rights provided in a 1989 law.

There are 400 to 500 whistle-blower cases in the government every year, and advocacy groups argue that federal agencies often try to silence or discredit employees who speak out about waste and mismanagement.

The letter was organized by the Government Accountability Project, Public Citizen, the Project on Government Oversight and the Union of Concerned Scientists. Members of the coalition include religious, consumer, civil liberties, environmental and other groups.

Any compromise, the coalition said, should retain key proposals in the House and Senate bills, including providing federal whistle-blowers with the right to a jury trial in federal court and stronger safeguards for federal scientists who report efforts to misrepresent or suppress research.