NEW YORK, United States — Gap Inc. and Sears Holdings Corp. are being questioned with 11 other retailers by New York's attorney general over possible use of on-call shifts requiring hourly workers to make themselves available on short notice.

New York Attorney General Eric Schneiderman sent letters to the retailers on April 10 seeking information about their use of such shifts and warning the companies that the practices may violate a state employment law. The attorney general has received reports that a growing number of employees, particularly in the retail industry, must work such shifts, which require them to check in as little as a few hours in advance to see if they are needed, according to the letters.

“Unpredictable work schedules take a toll on all employees, especially those in low-wage sectors,” Terri Gerstein, chief of the office’s labor bureau, said in the letters. Without a more definite schedule, on-call workers may struggle with childcare or elder-care arrangements, could suffer stress, and may have difficulty managing other aspects of their lives, Gerstein said.

Retailers, seeking to maximize efficiency, have been increasingly using software to help forecast staffing needs on a short-term basis. Schneiderman’s office questioned the retailers in the letters about whether they used certain computerized scheduling systems.

By Christie Smythe. Editors: Michael Hytha, Douglas Wong.