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By retaking control of the House in November, Democrats gained the power to demand President Trump’s tax returns. So far, they have refused to use that power. That refusal has become the subject of criticism from legal experts and progressive activists.

Why are Democrats holding back? There is one explanation that makes some sense: They believe that Robert Mueller, the special counsel investigating Trump, will issue a report very soon, and they want to learn what’s in it before starting a fight over the tax returns. A Mueller report could include some of the same information in those tax returns.

Yesterday, my colleague Ian Prasad Philbrick called the office of Richard Neal, the Massachusetts congressman who, as chair of the House Ways and Means Committee, has the authority to demand the tax returns. Ian asked why Congressman Neal had not yet done so.