Today a federal tax official provided House Ways and Means Committee members some details about how the Internal Revenue Service will review whether the political activities of shadowy nonprofit groups conflict with their exempt status.

The answer: slowly, according to the IRS Deputy Commissioner for Services and Enforcement Steven Miller, one of the witnesses at the hearing.

He said the IRS has decided to consider whether it would issue new guidance to the groups. And if the agency investigates groups, it looks at an entire year's worth of activity before determining whether an organization has violated tax laws, Miller ...