Quinton Mewborn, 39, was booked into the Morehouse Parish detention center this morning.
He resigned from the sheriff's office over the weekend.
The investigation -- conducted by State Police -- started after a complaint concerning unaccounted for funds raised by Little Angels of Northeast Louisiana.
State police say the group was founded last year by Mewborn and his wife, Stacey -- and was to assist families of children diagnosed with a connective tissue disorder.
Authorities say the investigation revealed about 4-thousand dollars was unaccounted for.
Investigators say Stacey is currently in the hospital, but when she's released, she'll also be charged with theft and conspiracy.