LOS ANGELES — Despite efforts by supermarkets to regulate the sale of alcohol to minors, self-checkouts allowed such purchases among nearly 20% of consumers in a study conducted by graduate law students at the University of California here and presented in partnership with a local group has been critical of Tesco’s Fresh & Easy chain.

According to the study, checkouts that are supposed to lock when alcohol is scanned — preventing a customer from completing the transaction until an employee has checked his identification and assessed his degree of intoxication — did not lock; it also said that, in some instances, customers were able to override the system by swiping a credit card or scanning other items.

The study also found a lack of adequate supervision of self-checkouts, with only one employee working the self-checkout area in 60% of store visits by survey teams, and no employee at all in 5% of the visits. In addition, although store personnel are supposed to check IDs for anyone who looks under the age of 30, the study said 32% of consumers under age 30 were not asked to show identification; further, it said there was eye contact (to determine possible intoxication) only 39% of the time; and employees did not ask questions of consumers in 23% of instances.

In the report Scott Cummings, a law professor at UCLA, recommended that state and local leaders take action “to address this situation and ensure that minors and people under the influence cannot obtain alcohol at grocery stores that operate self-checkout registers.”

The study, done in April, encompassed 97 visits to 34 grocery stores in Los Angeles and Orange counties. It was presented by the UCLA class and the Los Angeles Alliance for a New Economy, a group that advocates for worker benefits and seeks to encourage supermarket development in low-income neighborhoods. It has in the past been critical of Fresh & Easy, which employs a minimal staff and uses self-checkout exclusively.

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