Thank you for your questions.
North Carolina law does not require employers to provide employees with sick leave benefits, either paid or unpaid. If an employer chooses to provide sick leave benefits, it must comply with the terms of its established policy or employment contract
An employer in North Carolina may be required to provide an employee unpaid sick leave in accordance with the Family and Medical Leave Act or other federal laws.
Thus, here the question is whether the employer has a written policy on whether it may deduct your sick days from your vacation. The law would allow your employer to do what it has done, unless the employer has promised you that it would not do that.
The law in North Carolina heavily favors the employer in almost every situation. If your employer does not offer you paid sick days, then you can either take the vacation days to have paid time off, or you will need to take unpaid leave under the FMLA
In regard to your employer docking your vacation days even though you were answering phone calls at the emergency room, you do have an argument that the employer owes you pay for this day, as you continued and were required to work while you were "off". Thus, technically, you were on call
and were not off duty. This would be a claim you could make in small claims court, since you are an exempt employee.
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