re: #905 Bagua

Correct, fortunately Americans have constitutional protections which the Brits lack. Pity for them. But while Americans don’t have to worry about such things being mandated, sometimes things that are permitted constitutionally have to be made illegal to deter unacceptable behaviour.

Yes. People may want to criticize the Oklahoma law however they have the right to create such a law under the 10th Amendment.

Here’s a more practical example I found in Wiki:

The status of foreign law

Generally, when the court is to apply a foreign law, it must be proved by foreign law experts. It cannot merely be pleaded, as the court has no expertise in the laws of foreign countries nor in how they might be applied in a foreign court. Such foreign law may be considered no more than evidence, rather than law because of the issue of sovereignty. If the local court is actually giving extraterritorial effect to a foreign law, it is less than sovereign and so acting in a way that is potentially unconstitutional…

On the other hand, it could mean that the rule is being applied to a factual situation that occurred beyond the territory of its state of origin. As an example of this situation, one can think of an American court applying British tort statutes and case law to a car accident that took place in London where both the driver and the victim are British citizens but the lawsuit was brought in before the American courts because the driver’s insurer is American. One can then argue that since the factual situation is within the British territory, where an American judge applies the English Law, he does not give an extraterritorial application to the foreign rule. In fact, one can also argue that the American judge, had he applied American Law, would be doing so in an extraterritorial fashion.

At best it can only be accepted as evidence. That is if the judge allows it. However, under no circumstances should foreign legal precepts (both secular or theological) be allowed.

Why would they make such a law? Well, there are those that may want to apply it in our courts. For example:

International Law in Domestic Courts: A Conflict of Laws Approach
Cornell Law Faculty Working Papers - 2009

[The] parallel with conflicts changes international law in domestic courts from a specific problem addressed by international and constitutional lawyers into a general problem of relativism – which, we argue, conflict of laws is uniquely positioned to address. Here, the technicality of conflict of laws is not a shortcoming but a strength. The “conflict-of-laws machine,” we argue, is a way to reach a result without yielding to arbitrariness in the face of otherwise insurmountable complexity. Accordingly, we describe our larger project as “theory through technique.” This project will use private international law as a way of thinking through problems of legal, political and cultural relativism, including multiculturalism and transitional justice, as well as international law in domestic courts…