Big deal. The US and every other contry routinely withdraws jurisdiction from the International Court of Justice. The ICJ is something of a joke in legal circles to begin with. It exists mostly for political grandstanding since its decisions cannot be enforced.
"'The State of Texas believes no international court supersedes the laws of Texas or the laws of the United States,' Mr. Strickland said. 'We respectfully believe the executive determination exceeds the constitutional bounds for federal authority.'"
There is this thing called the treaty power in the Constitution. One treaty we entered into specifies that nationals who are arrested have a right to meet with consulate personnel. Texas as a state, is legally bound to go along with federally approved treaties. Unfortunately, Texas seems to be too lazy to comply with legitimate federal law. Texas should follow the law just like everyone else and quit its whining.
If we don't follow the treaty, then the next time an American gets arrested in Mexico, Mexican authorities may very well decline to uphold the American's rights under the treaty. (This is the legal principle of reciprocity - if we breach a treaty with Mexico, they get to breach that same treaty with respect to us). Remember this the next time you visit Mexico and see the policia taking an interest in you.