Sec. 6. An owner of a dog is exempt under section 4 of this chapter if the dog commits an act described in section 4 of this chapter during the period that the dog is owned by:
(1) the United States;
(2) an agency of the United States; or
(3) a governmental entity (as defined in IC 34-6-2.1-77);
and the dog is engaged in assisting the owner or the owner's agent in the performance of law enforcement or military duties.