House Democrats are expected to take pot shots at the 2017 tax law, including the smaller refunds many are receiving this year, during a Feb. 13 hearing focused on the middle class.

The hearing, to be held by the House Ways and Means Subcommittee on Select Revenue Measures, is the opening act of a House Democratic effort to re-examine aspects of the new tax law and ultimately build a case for why provisions in the new code need to be tweaked or changed.

The hearing comes at an opportune moment for Democrats, as some taxpayers discover that they...