House Democrats are preparing a bill that would require presidential candidates to release 10 years of tax returns, just for starters. The planned legislation would also require presidential candidates to disclose details of any offshore accounts or investments they had and disclose assets held by IRAs or 401(k) plans. Does any of this sound familiar?

"The stunning lack of transparency from someone in pursuit of the highest office in the country highlights the need to change the law to require fuller disclosure," Rep. Sander Levin said in a statement. "For decades, presidential candidates have voluntarily provided a thorough accounting of their tax returns and finances, as they should. But we clearly cannot continue to rely solely on the willingness of a candidate to disclose fully what the public has a right to know about the candidate’s financial record."

Levin also named names, calling on Mitt Romney to release his tax returns because "The American people should not be left to wonder what he is not disclosing and why not."

In theory there are two ways we won't be left to wonder: if Romney is forced by law to disclose, or if he concludes that the public opinion penalty for not releasing his tax returns will outweigh the damage they can do. Based on his continuing refusal, though, it seems like Romney is about as likely to release what every other presidential candidate in recent memory has released as John Boehner is to allow the House to vote on this bill.

(For further discussion, see Brainwrap's diary.)