Hello again, David.
It does sound as though it is time to be more proactive about this. The employer is not obligated to discipline the employee for making the false statements and they may be concerned about a potential claim of discrimination
being filed against them by this co-worker since you were promoted and she is not.
So it would typically be best for you to retain a local employment law
attorney to communicate a demand to this co-worker. It does sound as though she is engaging in defamation as well as intentionally interfering with your business relations, which gives rise to another tort claim against her.
A letter from your attorney threatening litigation if she does not cease such conduct immediately may be enough to resolve the situation if she does wish to avoid a lawsuit against her.
If not, then you certainly could file suit for damages you have sustained as a result of her conduct. You could also request injunctive relief from the court, preventing her from continuing to engage in such conduct.
Here is a link which sets out the elements of defamation under NY law:
Here is another link which discusses the tort of interference with business relations:
I hope this helps clarify the situation for you. Please remember to rate my service once you have all the information you need so I will be compensated for my time from the deposit you posted with this website. If you have any other questions, please ask me – I’ll be happy to respond. Thank you!