Minn. Stat. § 179.42: UNLAWFUL ACT AND UNFAIR LABOR PRACTICE.

It is an unlawful act and an unfair labor practice for any person or organization to combine with another, to cause loss or injury to an employer, to refuse to handle or work on particular goods or equipment or perform services for an employer, or to withhold patronage, or to induce, or to attempt to induce, another to withhold patronage or other business intercourse, for the purpose of inducing or coercing such employer to persuade or otherwise encourage or discourage its employees to join or to refrain from joining any labor union or organization or for the purpose of coercing such employer's employees to join or refrain from joining any labor union or organization.