N.J. Stat. § 54:38-15: Constitutional construction

If for any reason any section or any provision of this chapter shall be questioned in any court, and shall be held to be unconstitutional or invalid, the same shall not be held to affect any other section or provision hereof. If for any reason any section, or provision, or the chapter in its entirety, shall be held to be unconstitutional or invalid, the same shall not be held to affect or invalidate, in whole or in part, any inheritance, succession or legacy tax laws of this state either heretofore or hereafter effective.