It passed, it is law.

I belive the constitution is law as well, no?

I don't think you understand how the law works. It was made a law, but it was deemed unconstitutional. Laws are difficult to ratify and even more difficult to get rid of, so a lot of times, they will be struck down by a court decision, but not taken off the books. If it's the Supreme court making the decision, that's precedence every other court will use. Again, just google Sunday laws.

But they aren't enforceable. Murder is. And murder is not a constitutional right.

If you kill someone from another country, you will get detained and charged. Look at Amanda Knox.

And if others kill someone here, America has arrested and charged many people. America detains illegals all the time. In fact, 64% of illegal immigrants are in jail for just being illegal. When we're not deporting them, we're sentencing them and keeping them in our prisons. Diplomatic immunity doesn't have to do with being from another country so you can't be charged by America. Sure, we can extradite people and have their country charge them, but we don't have to.

http://www.fairus.org/issue/examples-of-serious-crimes-by-illegal-aliens

No lawyer, DA or police would even attempt to charge the lady in this post, because the constitution supercedes any law in the land. Period. Yes, it's socially unacceptable to piss on a flag. No, it is not punishable. Period. Nothing is higher than the constitution, so she isn't hiding behind something to do something illegal. She is expressing her fundamental right and therefore she can't be punished. This isn't my opinion on if it's right or wrong. I personally think it is vulgar and she was acting like an asshole.

But, according to law, she CAN'T be punished, regardless of the Flag Protection Act.

Yes, the difference is being able to understand which situations fall under which laws.

And the Supreme Court has ruled that the situations that would be outlawed by the flag protection act are protected by the constitution.... Hence why it's unconstitutional and can't be enforced...

But there has been cases of people being able to escape trails for crimes up to murder through diplomatic immunity. Does this make murder acceptable, or is it gross abuse of the legal system?

The analogy you are making is flawed at best. Diplomatic immunity is not a human or constitutional right...it is given to foreign (people not governed by our constitution) diplomats. Yes, people can get away with all types of crimes (sometimes murder), but the country allows this (privilege as it's not given all willy nilly to any foreign joe) in order to gain the same privileges; our diplomats have the same immunities in other countries. In some cases, that privilege can be revoked. We've tried diplomats for murder in this country. But it's true that some have abused the legal system, because they've had diplomatic immunity.

The constitution, on the other hand, is the top law of the land for our citizens, and the particular subject we're debating, The Flag Protection Act 0f 1989, has been struck down by the Supreme Court in lieu of it contradicting the constitution. In this case, the chick isn't abusing the legal system like a diplomat might if he committed a crime while protected by diplomatic immunity. The constitution isn't some shield from the legal system. It is the basis for our legal system, so if a law is struck down by it, it's no longer enforceable. That is the key difference.

Apples to oranges.

It's an example of the abuse of laws that are meant to protect instead of allowing anyone to do whatever they want.