Employers can require employees to speak English at work, as long as they enforce the rule across the board.
What they can’t do: Allow some employees to use one foreign language but punish others for using a third language.
Recent case: Marie worked in a hospital office. Marie is from Haiti and speaks French as her primary language. She was reprimanded for sometimes speaking French in the office.
She sued, alleging national-origin discrimination and other forms of bias.
The hospital pointed out that it forbade all foreign languages and had reprimanded some employees for using Spanish at work. (It pointed out that it was fine for employees to use another language to assist patients.)
The court agreed the hospital was within its rights to insist on English as the language to use while working in the office. (Joseph v. North Shore University Hospital, No. 11-1014, 2nd Cir., 2012)
Final note: Don’t ban the use of another language during breaks and other off-duty time. Employees should be allowed to use whatever language they prefer among themselves while not working. That may make some managers uncomfortable, but don’t ban it unless there have been other, specific problems, such as using another language to sexually or otherwise harass co-workers.
Doing so may constitute discrimination based on national origin, and may even be an unfair labor practice if the employees are discussing working conditions in their native tongue.