Missouri Revised Statutes Title VII. Cities, Towns and Villages § 71.013. Train crewman not to be personally liable under city ordinance or state statute for blocking crossing, when

1. No member of a railroad train or yard crew shall be held criminally guilty of any responsibility of violating a state law or any municipal ordinance regulating the occupying or blocking of any street or highway railroad crossing-at-grade by trains or cars, upon reasonable proof that his action was necessary to comply with the order or instructions, either written or verbal, of his employer or its officers or supervisory officials;  and provided, that nothing in this section shall relieve the employer or railroad from any responsibility placed upon said employer or railroad by any such state law or any municipal ordinance.

2. Every person, firm, company, or corporation, operating a railroad as a common carrier in the state of Missouri and violating the provisions of this section, shall be fined not less than fifty dollars for each separate offense.