Authorities said the scheme involved using a home computer to produce UPC bar codes for cheaper products and slipping them over the real codes on high-priced items. The suspects then allegedly sold the merchandise, or returned it for refunds or store gift cards that also were sold.
The Uniform Product Code identifier brings up a product's name and price on a store cashier's screen.
Authorities said they're still calculating the total stolen from Wal-Mart and two other unidentified retail chains by the four suspects and up to 30 accomplices.
"They were ranging all over the country," Sumner County District Attorney Ray Whitley said.
Arrested Tuesday on charges of theft of more than $60,000 were sisters Julie Marie Simmons, 35, and Laura Simmons Howerton, 39, and their husbands Michael Poore, 29, and Dewey Howerton, 39. The four share a house in the Nashville suburb of Portland.
The ring avoided detection in part by visiting stores at the busiest times, Portland Police Detective Don Hardin said.
Hardin, who declined to name the other chains at the companies' request, said other arrests could come as soon as next week.
Authorities began making their case in January after investigators in neighboring Macon County found about $10,000 in stolen Wal-Mart merchandise and an informant who led them to the two couples.
Wal-Mart Stores Inc. spokeswoman Sharon Weber declined to comment on the specifics of the case, but said the company has been active in the investigation.
Authorities say they believe the ring struck Wal-Marts in Alabama, Arkansas, Florida, Georgia, Illinois, Indiana, Iowa, Louisiana, Mississippi, Missouri, Nebraska, North Carolina, Ohio, Oklahoma, South Carolina, Tennessee, Texas, Virginia and West Virginia.
The four were in jail Thursday awaiting a Jan. 5 court hearing. They face from eight to 20 years if convicted on the theft charges. Authorities say further charges are likely.
By Colin Fly