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39 U.S. Code § 5603 - Transportation of mail by vessel as freight or express

The Postal Service may require that mail be transported by freight or express when—
(1)
there is no competition on a water route and the rate or compensation asked is excessive; or
(2)
no proposal is received.
A common carrier by water that fails or refuses to transport the mail when required to do so under this section shall be fined not more than $500 for each day of refusal.
(Pub. L. 91–375, Aug. 12, 1970, 84 Stat. 773.)
Statutory Notes and Related Subsidiaries
Effective Date

Section effective July 1, 1971, pursuant to Resolution No. 71–9 of the Board of Governors. See section 15(a) of Pub. L. 91–375, set out as a note preceding section 101 of this title.