(NEW YORK) -- We used to call it shoplifting, but these days the foot soldiers of retail crime rings are known as boosters. Police even have an acronym for these operations: ORC, which stands for Organized Retail Crime.
"It's just like a Fortune 500 company," said Sergeant Eric Lee of the Gardena Police Department in Gardena, Calif. "All of this is just organized."
Police say big retail stores, from Walgreens to J.C. Penny, are getting hit by highly sophisticated shoplifting networks that steal and resell everything from underwear to razors to milk. According to the National Retail Federation, theft can amount to annual losses as high as a $37 billion for retail businesses.
"Every store in every city has to go through this," Lee said. "They wait until no one's paying attention and they walk out."
Tide detergent is currently a hot target because it is compact, expensive and easy to sell on the streets for profit, police said. The street name: "liquid gold."
"Sometimes we get rings that just do alcohol," Lee said. "And then we get some that do just meat and seafood."
Investigators say boosters move the loot for cents on the dollar to fencing operations -- the black market resellers of the stolen goods -- which sell the stolen merchandise in plain sight in stores. Boosters, fencers, Mr. Bigs, all of those involved in these shoplifting operations can potentially make millions a year from boosting and re-selling stolen goods.
And Mike Swett is on the case. A former Riverside County sheriff's deputy in Los Angeles, Swett was badly injured in a car wreck and now works as a full-time private investigator on the ORC beat who has worked with Target, Marshalls and T.J. Maxx. Stores hire him to do his own undercover police work, catching thieves before involving local law enforcement.
"Kind of like working a narcotics case, it's like you've got low-level, mid-level and then top dog," Swett said. "We like to go after the top dog and the only way to get to the top dog is mid-level first."
Swett said he has been casing two joints in L.A. for months, both alleged to be mid-level fencing operations. Nightline was invited to ride along with him when he sent undercover agents in for a final reconnaissance mission.
At some stores and shopping malls, clerks do little to stop shoplifters and often let them run, which has contributed to the growing fencing operations.
"[The stores] don't want their employees to get injured," Swett said. "So oftentimes they will call the police, but by the time we get there they are already in their car and they are gone."
This leaves professional investigators like Swett to put the pieces together and bust open the gangs to lead over-stretched police departments to the prey.
When raid day arrived, a motorcade of squad cars departed from the Gardena, Calif., police department and pulled up to one fencing operation. Swett said the merchandise being sold was boosted goods.
"There is Victoria's Secret, expensive Victoria's Secret, the gift sets," he said, pointing down a line of tables. "J.C. Penny, Miramax, its real stuff not counterfeit."
He spotted a bottle of Katy Perry brand perfume, which usually retails for around $90 but one seller had it priced at $59.
"She probably paid $10 for it," Swett said.
Inspectors from various stores swarmed the place and all of the merchandise was photographed. Police handcuffed the accused and it was on to the next target.
In another jurisdiction halfway across the country, investigators in northern Indiana have a secret warehouse that is packed with millions of dollars worth of stolen merchandise -- one of many across the United States.
Its location is kept secret because busting in would be a booster's dream, a one-stop shop. This is also the headquarters for Walgreens' Organized Retail Crime Division run by director Jerry Biggs. Biggs said more than 40 boosters can feed one fencing operation. One recent ring they busted was making $17 million a year.
"This stuff here," Biggs said, gesturing to the thousands upon thousands of bottles of lotion, baby formula and medical supplies. "Most of it was taken within just weeks. Probably took us about six months to work the case, following them to four different states continuously."
Pins in a map stuck to the wall mark shoplifting hot spots. Flow charts connect members of various gangs.
Biggs' library of surveillance tapes is astounding. One tape showed a man wearing a suit in a Texas Walgreens swiping a tray of diabetic test strips -- a total value of $1,000.
Two days later, Biggs said that man was stopped by traffic cops with $4,000 worth of medicine in the trunk of his car. He was charged with possession of controlled drugs and stolen property.
Another Biggs video showed two women who seemed to have the keys to display cases in another Walgreens, which they unlocked and emptied, making off with the merchandise. Police are still looking to question them.
Biggs and his team are the James Bonds of retail crime, armed with tracking devices, radios and hidden cameras, including visor cams that Biggs said can monitor what is going on in a 360-degree radius. A booster might think he is out the door and home free, but not always.
"With today's technology, I can have your face pretty much throughout the country in less than 10 minutes," Biggs said.
Back in Los Angeles, the people at the fencing operation were arrested for possession of stolen property. Formal charges still pending their court date.
Another operation completed, but for Swett, the work goes on.
"Could be nothing, could be something, but that's a lot of stuff" he said, as he starts to videotape a suspicious van being loaded in a store parking lot during one of his recent stake-outs.
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