The doctrine of "at will" employment holds that a person can be fired from their job at any time for no reason, a bad reason, or any reason at all; with or without notice.  With at-will employment in NY, the company handbook is meaningless.  Even if an employee complies with all policies relevant to an issue, an employer is still free to terminate the employee because its policies are just that, policies; non-binding recommended courses of action.  They can be followed or not, at the employer's discretion.  In other words, an employer may terminate an employee in violation of its own policies.