A California bill would require anyone buying alcohol to pay a cashier, instead of going through a self-checkout aisle. The bill’s supporters say it would prevent minors from buying alcohol. The bill, which has been passed by the state Assembly, is scheduled to be voted on by the state Senate this week, according to the Los Angeles Times.

Proponents of the bill point to a study conducted last year by the Center for Alcohol and Drug Studies at San Diego State University, which included young adults who were judged to look younger than 23. They were sent to 216 stores with self-checkout lanes in California, and tried to buy alcohol through those lanes. Overall, 8.4 percent of purchase attempts resulted in a failure to ask for identification to purchase alcohol. Most of those failures were rectified by store employees, however. The study concludes the growing number of self-checkout options at supermarkets is a potential source of alcohol for minors.

Chris Albrecht of California’s Department of Alcoholic Beverage Control, told the newspaper that routine, random checks over the last five years, using shoppers under age 21, showed the incidence of sales violations at both automated checkouts and staffed checkouts was about 15 percent. “We don’t see any evidence that the self-service checkout aisles create any kind of increase in youth access to alcohol,” he said.

Supermarket executives oppose the legislation, saying unions are using the bill to fight labor-saving technology.