Can my employer fire me for no 'valid' reason?

 Yes. New York State is an employment-at-will state. The employment-at-will doctrine is a judicially created common-law rule that states where employment is for an indefinite term, it is presumed to be at-will. As the name suggests, the employer can fire an employee for any reason, or no reason, without legal recourse, just as the employee is equally free to end an employment relationship at any time. The employment-at-will doctrine is firmly established in New York State, and absent an express agreement, New York courts will uphold the law.

The doctrine, however, has evolved over the years providing workers with additional job security and protection. Employees are protected if they have a contract that outlines specific allowable reasons for termination or if he/she is fired for discriminatory reasons. The New York State Division of Human Rights protects an employee from discrimination.

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New York State Division of Human Rights
URL: http://www.nysdhr.com