Earlier quoted context omitted.
> Interpretation isn't law, so in any legal dispute over the > IRS actions under the current interpretation, the law which > would be controlling is not retroactive. This is to me a very weak argument (not that I disagree that this may be the standard that is applied in practice). If the Congress passed a law saying "the IRS can set tax code as it sees fit" and the IRS proceeds to levy taxes all the way back to 1980…
> If the Congress passed a law saying "the IRS can set tax code as it sees fit" Then this would be an unconstitutional delegation of legislative authority to the executive. [0] Rendering the consideration of whether any executive action under it would constitute an ex post facto law moot -- if Congress purports to delegate enough power to the executive that retroactive executive action under it would be an ex post fa…
And yet this is what we seem to be experiencing in this case, where the IRS can make a policy interpretation retroactively to the tune of $6 billion for a single taxpayer. Your source indicates that congress allows the IRS to decide tax policy, but since tax evasion is itself a crime it seems to indirectly violate the ex post facto law prohibition.