It was designated as the central facility for processing applications for tax-exempt status that required further review.

WSJ: IRS Apologizes for Scrutiny of Conservative Groups

It found IRS managers had allowed "inappropriate criteria" to be developed and stay in place for more than 18 months, resulting in "substantial delays" in processing applications for tax-exempt status, and requests for "unnecessary information", such as lists of donors.

BBC: IRS commissioner quits over conservative tax scrutiny

Tea-party groups have complained often to lawmakers about IRS scrutiny and delays in processing their applications for 501(c)(4) status.

WSJ: IRS Apologizes for Scrutiny of Conservative Groups