Investor advocates are getting nervous about a lot of things being discussed on Capitol Hill these days, including ideas that could potentially put accounting rules under more political authority.

The Center for Audit Quality, the Council of Institutional Investors, and an arm of the U.S. Chamber of Commerce sent a letter to the leadership of the House Financial Services Committee to remind them that the Financial Accounting Standards Board is overseen by the Securities and Exchange Commission because it’s supposed to be independent of the political process. Accounting rules are supposed to be written with investors in mind, and the SEC is charged with keeping capital market safe for investors, the groups say.

The House committee aired a number of ideas during a recent mark-up session to revise H.R. 3904, the Financial Stability Improvement Act of 2009, among them a suggestion that perhaps FASB should be overseen by a new systemic risk regulator. The relocation of FASB under another authority has been floated before in Congress, and that makes groups like the CAQ, CII, and Chamber a little antsy.

Investors rely on FASB’s accounting rules to produce financial statements that are the basis for big investment decisions, the groups say, and they accept those financial statements as legitimate because of the independence of FASB’s process for writing the rules. To remain confident in financial reports, “the process by which accounting standards are developed must be free—both in fact and appearance—of outside influences that inappropriately benefit any particular participant or group of participants in the financial reporting system to the detriment of investors, businesses, and capital markets,” the groups told the House committee.

The investor advocates worry that putting FASB under the jurisdiction of a systemic risk regulator would cause accounting rules to be viewed more narrowly from the perspective of a handful of large companies.