It is shown that the topological massive and ''self-dual'' theories, w
hich are known to provide locally equivalent descriptions of spin 1 th
eories in 2 + 1 dimensions, have different global properties when form
ulated over topologically non-trivial regions of space-time. The parti
tion function of these theories, when constructed on an arbitrary Riem
annian manifold, differ by a topological factor, which is equal to the
partition function of the pure Chern-Simons theory. This factor is re
lated to the space of solutions of the field equations of the topologi
cal massive theory for which the connection is asymptotically flat but
not gauge equivalent to zero. A new covariant, first order, gauge act
ion, which generalizes the ''self-dual'' action, is then proposed. It
is obtained by sewing local self-dual theories. Its global equivalence
to the topological massive gauge theory is shown.