The heads of three of the most influential business groups have once again asked members to resist calls by activists to disclose their political donations beyond what the law requires.

In a joint letter, U.S. Chamber of Commerce CEO Tom Donohue, National Association of Manufacturers CEO Jay Timmons and Business Roundtable President John Engler warned members against what they said is a concerted campaign to erode "the business community's voice" in the political process. The letter was sent in October but was made public Tuesday by the Center for Public Integrity, an investigative journalism organization.

The three leaders note that in recent years, activist groups have teamed with like-minded investors to pressure groups to disclose their spending on attempts to sway public policy.

"In practical terms, this translates into getting companies to disclose increasing amounts of information about their involvement in public policy, including membership in trade associations, with the ultimate goal of using this information to name-and-shame companies into either curtailing or eliminating their involvement in public policy debates altogether," the executives said.

The three leaders have issued similar warnings in the past. In 2013, they released a joint letter that urged members to fight a proposed Securities and Exchange Commission rule requiring public companies to fully disclose to investors their spending on advocacy, including contributions they make to associations and other business groups.

Opponents of the rule convinced Congress to slip in a provision in the recently adopted federal budget bill that prevents the agency from enacting the measure.

One of the groups most active in calling for disclosure is the Center for Political Accountability. Bruce Freed, who leads CPA, told CPI the criticism from the Chamber and other groups wasn't unexpected.

"The reason: it is leading to the broader disclosure of company payments to trade associations, and the U.S. Chamber in particular. The Chamber has a deep investment in secrecy," he said. http://bit.ly/1JF3nGS

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