The Pending Texas Leal Execution and Consular Law  Peggy
McGuinness discusses the international and federalism legal
issues over at Opinio Juris.  Essentially, she notes, the issue
comes down to federalism and the avenues of a domestic remedy:
The problem for Leal and others whose death penalty convictions
were obtained following a clear and acknowledged violation of
U.S. obligations under the Consular Convention is not a lack of
clarity about consular law. The problem is the domestic remedy.
There are only two institutions remaining that can provide one
to Mr. Leal today: The U.S. Supreme Court, if it accepts the
very strong argument of Leal’s attorneys and the Solicitor
General that the Court should invoke its power under the All
Writs Act to stay the execution until the proposed
jurisdictional and remedial statute (the Consular Notification
Compliance Act) is adopted by Congress, or Governor Perry.