Asked this question to an enforcement officer.. You can shoot a deer off your front step. The 400 meters does not apply to your own dwelling.
Confirmed.
46(3) The owner or occupant of a dwelling who is authorized
by a licence issued under this Act or the regulations
to hunt, trap or snare may discharge a rim-fire rifle,
centre-fire rifle or a shotgun loaded with ball or slug within
four hundred metres of his or her dwelling if the point of
discharge is more than four hundred metres from any other
dwelling and from any school, playground, athletic field,
dump or place of business.
Also worth noting..
46(5) Notwithstanding any other provision of this section,
a person who is authorized to hunt, trap or snare by
a licence issued under this Act or the regulations and who
has wounded any wildlife may discharge a firearm for the
purpose of taking that wounded wildlife within any distance
from a dwelling, school, playground, athletic field,
dump or place of business.
SOURCE:
http://www.gnb.ca/0062/PDF-acts/f-14-1.pdf