NYC Admin. Code § 8–107 provides: 1. Employment. It shall be an unlawful discriminatory practice: (a) For an employer or an employee or agent thereof, because of the actual or perceived age, race, creed, color, national origin, gender, disability, marital status, partnership status, sexual orientation or alienage or citizenship status of any person, to refuse to hire or employ or to bar or to discharge from employment such person or to discriminate against such person in compensation or in terms, conditions or privileges of employment.
In short, if your friend can show that he had an obligation as part of his job description
to report the violation of the employer's policies concerning taking time off during the work day, becoming intoxicated on the job, or similar, or that the terms and conditions of your friend's employment caused him to be terminated in a manner different that would be applicable to other supervisory personnel, then your friend would have a claim for unlawful discrimination
under NYC law.
Your friend needs documentation to support this claim. Though, even without copies of the employer's policies, the NYC Human Rights Commission could subpoena the documents -- but, the risk is that the employer may manufacture something to protect itself from liability, once it discovers that your friend does not have any independent copies of the employer's policies.
A complaint appointment may be made by dialing 311 (or (212) NEW-YORK) or(NNN) NNN-NNNN
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