"Senate Finance Committee Chairman Orrin Hatch (R-Utah) sent a letter to [IRS] Commissioner John Koskinen questioning the IRS's announcement that the agency would waive certain tax penalties under the [ACA].... Hatch asks that IRS explain what led to this new waiver program, how many taxpayers are expected to owe tax debt based on excess insurance subsidies, whether the Internal Revenue Service communicated with other agencies in creating the waiver program, and if there are plans for future waiver programs."