Michigan Compiled Laws, Chapter 423. Labor Disputes and Employment Relations § 423.16

Sec. 16. It shall be unlawful for an employer or any officer or agent of an employer (1) to interfere with, restrain or coerce employees in the exercise of their rights guaranteed in section 8;  1 (2) to initiate, create, dominate, contribute to, or interfere with the formation or administration of, any labor organization: Provided, That an employer shall not be prohibited from permitting employees to confer with him during working hours without loss of time or pay; (3) to discriminate in regard to hire, terms or other conditions of employment in order to encourage or discourage membership in any labor organization; (4) to encourage membership in, or initiate, create, dominate, or contribute to a company union; (5) to discriminate against any employee because he has given testimony or instituted a proceeding under this act; or (6) to refuse to bargain collectively with the representative of his employees, subject to the provisions of section 26.  2