It is not considered stalking, though you may have a remedy. You do have an expectation of privacy inside your home. If your neighbor has cameras all around their house, you may be out of luck, though, because they have a stronger argument for security. However, if this is the only camera they have, I would seek an immediate TRO and get a hearing before a judge. It is more than likely that it will be taken down, depending on your jurisdiction. You will need to consult an attorney as soon as you can.
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