N.J. Stat. § 34:12-3: Employer shall not require employees to renounce membership in or refrain from joining society or brotherhood

No corporation doing business in this state shall require directly or indirectly that any individuals shall either individually or collectively, in any manner promise to renounce existing membership in a lodge, brotherhood, or labor organization of any kind, or promise to refrain from joining any such lodge, brotherhood, or organization at any future time.