The fiscal cliff has been used by the IRS as an excuse for the delay of tax refunds, but we may never know for sure. This article from Politico indicates that IRS furloughs could be to blame:
“Law-abiding taxpayers could shoulder the brunt of the blow when the sequester hits the Internal Revenue Service Friday — and tax cheats might find it easier to rig the system. It’s a little-discussed risk of the automatic budget cuts — and yet, another smack to the already battered 2012 tax filing season.”