[goorala]

No, tax returns are not fair game. The mental acuity of the President clearly is.

[RoosterRedux]

It's certainly fair game for Biden to respond to a tit-for-tat by asking to see his tax returns. Whether he "gets" to see them is another matter.

As someone upthread said, politics ain't beanbag. Biden can ask Trump if he's still grabbing pussy if he wants to. We aren't bound by the Marquess of Queensberry Rules.