ANGIE - A man convicted of molesting a child was able to walk free for about a month after he was mistakenly released thanks to a mathematical error at a Louisiana prison.

Arrest records say Brian Matherne, 66, still had seven years left of his nearly 30-year sentence when he was freed from Rayburn Correctional Center in Washington Parish on Feb. 1. He pleaded guilty to charges of molestation of a juvenile and aggravated crimes against nature in 2000.

Matherne was supposed to serve out his whole sentence without the possibility of an early release, and Department of Corrections officials didn't catch the "erroneous time calculation" until Feb. 27, when a prosecutor and a state lawmaker familiar with the case brought it to the agency's attention. 

"Brian Matherne was originally released based upon the application of general goodtime provisions, however DOC obtained the original court transcripts and confirmed that the court specifically restricted the application of goodtime to the sentence imposed," the department said.

A department spokesperson said Matherne was taken back into custody late Wednesday, March 2. He has since been booked back into Rayburn Correctional.