The outcome was a law which might be evaded with relative ease wherever public sanction was weak, but which nevertheless proved fairly effective in operation.
When slave prices rose to high levels after the war of 1812 systematic smuggling began to prevail from Amelia Island on the Florida border, and on a smaller scale on the bayous of the Barataria district below New Orleans; but these operations were checked upon the passage of a congressional act in 1818 increasing the rewards to informers.

Another act in the following year directed the President to employ armed vessels for police in both African and American waters, and incidentally made provisions contemplating the return of captured slaves to Africa.

Finally Congress by an act of 1820 declared the maritime slave trade to be piracy.[33] Smuggling thereafter diminished though it never completely ceased.
[Footnote 33: DuBois, _Suppression of the Slave Trade_, pp.

118-123.] As to the dimensions of the illicit importations between 1808 and 1860, conjectures have placed the gross as high as two hundred and seventy thousand.[34] Most of the documents in the premises, however, bear palpable marks of unreliability.

It may suffice to say that these importations were never great enough to affect the labor supply in appreciable degree.