Section 71-1935. Emergencies excepted

The  civil  and  criminal  liabilities imposed by sections 71-1929 and
  71-1933 of this title upon persons violating the provisions of titles  1
  through  11 inclusive and title 19 of article 17 and by sections 71-1929
  and 71-1933 of  this  title  shall  not  be  construed  to  include  any
  violation  which was caused by an act of God, war, strike, riot or other
  catastrophe as to which negligence or willful misconduct on the part  of
  such person was not the proximate cause.