[spellbanisher]

Originally Posted by Andrew H.

I don't see how. If extending copyright from life+50 to life+70 doesn't violate the copyright clause, I don't see how putting certain PD works in the life+70 category would violate it.

And this decision doesn't burden the 1st Amendment any more than the copyright clause already does.

I didn't say it violated the copyright clause; I said it made a mockery of it. The purpose of the copyright clause is to give private incentives to further the public good, specifically, to incentivize creation of new content that will eventually be in the public domain. This is affirmed by the House Report on the Legislation that implemented the Berne Convention in the US:

Under the U. S. Constitution, the primary objective
of copyright law is not to reward the author, but
rather to secure for the public the benefits derived
from the authors labors. By giving authors an incen-
tive to create, the public benefits in two ways: when
the original expression is created and . . . when the
limited term . . . expires and the creation is added to
the public domain. Id., at 17

http://www.law.cornell.edu/supct/pdf/01-618P.ZD1

There are several defenses, however, for the Congressional Power to extend copyright or remove works from the public domain. One defense essentially is that the copyright clause is so broad as to give virtually unlimited leeway to congress in how it tries to execute the clause, with the only restriction being that congress can't explicitly make copyright perpetual. This I think, however, makes a mockery of the clause; if congress continually retroactively extends copyright, then the copyright clause for all intents and purposes becomes a joke. I'm not saying this is an incorrect interpretation, just that this interpretation renders the clause meaningless.

Another defense is that there is precedent for the retroactive extension of copyright dating back to the first congress. However, I think Justice Stevens effectively dispels that defense:
http://www.law.cornell.edu/supct/html/01-618.ZD.html

Congress also passed the first Copyright Act, 1 Stat.
124, in 1790. At that time there were a number of maps,
charts, and books that had already been printed, some of
which were copyrighted under state laws and some of
which were arguably entitled to perpetual protection
under the common law. The federal statute applied to
those works as well as to new works. In some cases the
application of the new federal rule reduced the
pre-existing protections, and in others it may have in-
creased the protection.7 What is significant is that the
statute provided a general rule creating new federal rights
that supplanted the diverse state rights that previously
existed. It did not extend or attach to any of those
pre-existing state and common-law rights: That congress,
in passing the act of 1790, did not legislate in reference to
existing rights, appears clear..
.
Congress set in place a federal structure gov-
erning certain types of intellectual property for the new
Republic. That Congress exercised its unquestionable
constitutional authority to create a new federal system
securing rights for authors and inventors in 1790 does not
provide support for the proposition that Congress can extend
pre-existing federal protections retroactively...

Moreover, members of Congress in 1790 were well
aware of the distinction between the creation of new copy-
right regimes and the extension of existing copyrights.
The 1790 Act was patterned, in many ways, after the
Statute of Anne enacted in England in 1710.

In other words, the Copyright Act of 1790 created a new regime of Federal Copyright; it did not extend the existing regimes of state copyrights, and therefore, cannot be interpreted as a retroactive extension of copyright.

Still another defense is that congress has repeatedly retroactively extended copyright in the past, and therefore it has the constitutional authority to do so. Stevens also shoots that argument down quite effectively:

as our decision in INS v. Chadha, 462 U. S. 919 (1983), demonstrates, thefact that Congress has repeatedly acted on a mistaken
interpretation of the Constitution does not qualify our
duty to invalidate an unconstitutional practice when it is
finally challenged in an appropriate case.

Still another defense, and the one that I think was the ultimate impetus for the Eldred Ruling, was one of practicality; basically, overruling Congress on the CTEA would open up a can of worms on a whole slew of ip laws and international agreements. However, it is not clear that that opening that can of worms would impose anywhere near the cost that retroactively extending copyright did.