Sometimes people younger than 21 ask strangers to go inside liquor stores and buy them alcohol.
No arrests were made in a shoulder tap operation Saturday night for the first time since Walnut Creek police launched the project, police said.
The operation uses underage decoys who ask patrons outside liquor or convenience stores to buy them alcohol under the supervision of a peace officer, police said. The decoys indicate that they are minors and cannot purchase the alcohol.
All of the previous shoulder tap operations resulted in arrests or citations for furnishing alcohol to a minor, public intoxication, or furnishing tobacco products to a minor, Walnut Creek police said.
"The word is getting around that (the) Walnut Creek Police Department is cracking down on people giving alcohol to juveniles," one of the underage decoys told police.
The operation, which is part of the Department of Alcoholic Beverage Control's Minor Decoy/Should Tap Operation Project, is conducted by the Community Policing Team.
The project is funded by the California Office of Traffic Safety through the National Highway Traffic Safety Administration.