o its enactment, was held not to deprive the
producers of property without due process of law since it operated, not
upon production, but upon the marketing of the product after the act was
passed.[175]

The validation by statute of a prior mortgage of personal property
invalid because improperly recorded, did not deny due process of law to
a judgment creditor seeking to levy an attachment on the mortgaged
property.[176] Nor was property taken without due process of law by a
statute of New Mexico territory, permitting disseisin of real property
to ripen into title after ten years.[177] An order of the military
governor of Porto Rico reducing the period during which the possession
of real estate must continue, to permit an _ex parte_ conversion of an
entry of possessory title into record ownership was construed to apply
only where there still remained a reasonable opportunity for the true
owners to contest the claim. The Court said that any other construction
would permit a taking of property without due process of law.[178]

Rights created by statute are subject to qualification by Congress;
benefits conferred gratuitously may be redistributed or withdrawn at any
time.[179] Where Congress provided, in granting lands to a railroad,
that such land could be resold only to actual settlers, at a price not
exceeding $2.50 per acre, it could constitutionally, for breach of
performance, resume title to the lands while assuring the railroad the
equivalent of its interest.[180] An act making an appropriation for a
private claim which restricted the attorney's fees payable therefrom to
twenty per cent was valid although inconsistent with a prior contract
with the claimant allowing a larger fee.[181] Statutory restrictions on
compensation for services in connection with veterans' pensions or
insurance have been upheld.[182] An increase in the penalty for
production of wheat in excess of quota was not invalid as applied
retroactively to wheat already planted, where Congress concurrently
authorized a substantial increase in the amount of the loan which might
be made to cooperating farmers upon stored "farm marketing excess
wheat."[183]

Retroactive Legislation Disallowed

The due process clause has been successfully invoked to defeat
retroactive invasion or destruction of property rights in a few cases. A
revocation by the Secretary of the Interior of previous approval of
plats and papers showing that a railroad was entitled to