According to U.S. News, employers can indeed require doctors' notes when you use sick leave. However, they should not oblige the note to include a diagnosis or other private medical information; rather, the note should simply indicate that you were seen by a medical office and/or confirm your need to use sick leave.
But just because the law permits employers to require doctors' notes doesn't mean they should do that. Minor illnesses, for example colds and the flu, don't generally require a doctor's care, and requiring a doctor's note in order to use sick time disheartens employees from staying home when they're ill.
That's an unfair burden on truly sick employees, who will have to drag themselves to a doctor when a few days of resting in bed will cure them. This policy also drives up health care costs by pushing people to the doctor when they only need home care.
In the United States, most employers aren’t required to provide workers with paid sick leave. Employers for about half of all American workers do provide some form of sick leave. Traditionally, employers give employees separate leave for illnesses and injuries. Learn more about sick leave at hrhero.com.