Mr. Busk, who made $12.35 an hour, and a second worker filed a class action in 2010, asserting that wage and overtime laws were being violated. In friend-of-the-court briefs filed with the Supreme Court, retailers’ groups pointed to a study that found that 63 percent of stores checked bags and performed other antitheft checks at the end of the workday. The retailers expressed concern that if the court ruled for Mr. Busk, they would have to pay employees for that time.

In its brief, the temp agency, Integrity Staffing Solutions, argues that the security check and the related waiting time are part of the “preliminary” or “postliminary” activities that are not compensable under the Portal-to-Portal Act, which Congress passed in 1947. Integrity Staffing pointed to a 1956 Supreme Court case, Steiner v. Mitchell, involving the donning and doffing of work clothes at a battery-making plant. The court wrote that compensation was required for tasks that were “integral and indispensable” to workers’ “principal activities.”

Integrity Staffing wrote in its brief, “Time spent passing through a security screening is a paradigmatic example of an activity that is noncompensable” because it is “postliminary to employees’ principal job activities.” Its counsel of record is Paul D. Clement, one of the nation’s foremost Supreme Court practitioners.

Mr. Busk’s lawyer, Mark R. Thierman, disagreed. “The antitheft check is integral and indispensable because the company said you have to do it,” he said. “If the company tells you to do it, it doesn’t matter whether it’s related to what else you do on the job.”

Image A dispute between Jesse Busk and a temp agency he worked for is to be heard next week by the United States Supreme Court. Credit... Isaac Brekken for The New York Times

Mr. Thierman said that if an employer ordered a worker to do something, that work should be compensable, whether or not it was integral and indispensable to primary work activities. He cited a 2005 Supreme Court case, IBP v. Alvarez, which said that if a company required its employees to arrive at a particular time to begin waiting, even if there was no work to be done at that time, the waiting time would be compensable and not just preliminary.