The district court for the Middle District of Florida dismissed an indictment under the Adam Walsh Act because Congress was unauthorized to enact the statute under the Interstate Commerce Clause. The case is United States v. Powers. Doubtful it would apply to Indian Country, but interesting nonetheless.
Update — Dec. 17, 2008 — This case, like one or two others, is likely an aberration. It is far more likely than not that the Adam Walsh Act is constitutional. For more information, see this website.
Turtle Talk 