Police busted four people who took just moments to decide on buying beer for the teenagers.
Investigators sit and watch the suspects come out of the stores, then walk over to his car and then give the teenagers their six-pack. Then officers follow their suspect and pull them over a few blocks from the store.
"The last few that we've had they really don't have a reason," said Clovis Police Sgt. Jim Koch. "They know, once we contact them, they know what they've done is wrong. They admit to being wrong for what they've done. They just say it's a lapse in judgment."
Clovis police keep a close eye on the operation the entire time, not only to witness the crime happen, but for the safety of their underage decoys.
"We watch them completely, through the entire event, make sure that their safety is the utmost importance to us," Sgt. Koch said. "And then when the purchaser does come out with the purchased beverages we wait til they walk away then we contact them."
Police say the sting works to reinforce to those supplying alcohol to minors the dangers of underage drinking.
You'll remember in the summer of 2010 six people died in a Central Fresno crash involving an 18-year-old drunk driver. The California Highway Patrol says a 21-year-old purchased alcohol for the underage driver who lost control of her SUV, which then caused a Greyhound bus to lose control and crash as well.
A $35,500 grant is funding "Operation Shoulder Tap." The money comes from the California Department of Alcoholic Beverage Control.
"This is just one tool to combat that and to let the public know that furnishing alcoholic beverages to minors is against the law, it's dangerous and we're not going to allow that to happen," said ABC investigator Jason Montgomery.
Four people were cited Tuesday for buying alcohol for those decoys. Clovis police say this is a yearlong campaign that includes checking alcohol licenses and seeing which stores will actually sell alcohol directly to teenagers.