The first thing that you need to know is that Virginia is an "at will" employment state. At-will employment means that without a contract, you have no contractual or other right to employment with the company. The company is entitled to fire you for any reason: a good reason, a poor reason, or no reason at all--as long as the company does not fire you for an illegal reason (race, gender, age, religion, etc...). But it extends beyond firing, to hiring, promotions, demotions, wage cuts and raises, disciplinary actions, and even scheduling. Unless you can show that this was done in violation of a contract, union agreement, or a clear violation of an unambiguous and binding clause against the employer, or that it was done because of some minority status (age, race, gender, religion, disability) that you have, then they do have this discretion. And they'd could still legally seek information from other employers. Creepy, weird, unethical, maybe, but it'd still be legal.
As far as you having a conflict of interest, A conflict of interest arises in the workplace when an employee has competing interests or loyalties that either are or potentially can be, at odds with each other. ... A conflict of interest causes an employee to experience a struggle between diverging interests, points of view, or allegiances. So if the part time employer competes with the full time one, and you are put in a position where you have to do something that necessarily harms one, to the benefit of the other, then that would be a conflict of interest. So if you're taking a client away from one to go to the other employer, even if you honestly feel that it's better for the client, that'd be a conflict of interest. Does that make sense? It's where you have divided loyalties essentially. But the point is that the employer can call the other employer to ask about that, as there's no law restricting either the inquiry by the full time employer or a disclosure by the part time employer.
Hope that clears things up a bit. If you have any other questions, please let me know. If not, and you have not yet, please rate my answer AND press the "submit" button, if applicable.
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