“Given your Department’s commitment to transparency and public input, we request that upon determining the specific changes the DOL will make to the Rule, you open a 15-30 day comment period prior to finalizing the Rule,” writes Polis in the letter.

“Otherwise, it will be harder to discern if the Rule can be implemented without unintended consequences, particularly regarding the provision of high-quality financial advice to low and middle income American families,” said Polis.

Polis, one of 52 House members of the New Democrat Coalition, a caucus that advocates for “pro-growth, fiscally-responsible” public policy, argued in the letter that the supplemental comment period would not disrupt DOL’s intention to implement a new rule by the end of 2016.

He also said the additional comment period would assure a new rule complies with the Administrative Procedure Act, the law first enacted in 1946 that oversees how government agencies implement new regulations.

Polis did not vote for the Retail Investor Protection Act this week, which passed through the House with only three votes from Democrats.

That law would insist the Securities and Exchange Commission be the lead regulator in crafting a new best interest standard, and require the DOL to postpone its rulemaking effort. The White House has vowed to veto the legislation if it were to pass the Senate.

Some opponents of DOL’s rule have suggested that the changes the agency is currently crafting are expected to be substantial enough to require the rule be pulled and re-proposed in order to comply with the APA.

Supporters of the rule say that argument amounts to nothing more than a stall tactic. Those who want to see the fiduciary rule killed are hoping to delay its implementation until after President Obama leaves office, on the hope a prospective Republican administration will craft a uniform fiduciary standard more favorable to Wall Street.

Dennis Kelleher, president and CEO of Better Markets, an advocacy for transparency in financial markets and a vociferous supporter of DOL’s rule, is circulating its own letter to members of Congress, urging them not to sign Polis’ letter.

“Regardless of the intentions of the authors and cosigners, the practical effect of reopening and extending the comment period would be the same outcome that the Koch Brothers and Wall Street are trying to achieve: delaying, watering down and, ultimately, killing a rule that protects hardworking Americans’ retirement savings,” according to the letter from Kelleher.

Polis’ letter says a supplemental shortened comment period has legal precedent, citing a 2001 decision by the Fifth Circuit Court of Appeals in Texas Office of Public Utility Counsel v. FCC.

Kelleher, who formerly was a litigator with Skadden Arps before serving as chief counsel to the Chairman of the Senate Democratic Policy Committee, says Polis’ request for an added comment period “has no basis in law.”

“Such a request may sound reasonable and benign, but courts strongly disfavor this practice because it degrades the rulemaking process by making agencies fear that they could find themselves ‘stuck in an infinite feedback loop of public comments’,” wrote Kelleher, referring to a 2003 decision from the Seventh Circuit Court of Appeals in Alto Dairy v. Veneman.

That ruling said, “the law does not require that every alteration in a proposed rule be reissued for notice and comment,” according to court documents.

In his letter, Kelleher added that a supplemental comment period will “needlessly delay and likely kill the best interest rule, which will help tens of millions of Americans who are trying to save for a dignified and secure retirement.”

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