Would breaking the law ever be justified?

Not necessarily. Even if there is a duty to obey the law, it might be trumped in specific cases by considerations of justice. Even if there is such a duty, then, unlawful strikes, whistle-blowing and other acts of disobedience might be justified.

How do you know if the law is unjust?

Any law that forbids transparency, and thereby attempts to compel, coerce or manipulate a responsible adults by withholding facts, OR any law that allows one person to control the actions of another (when those actions do no direct harm) is an unjust law.

Who said if a law is unjust A man is not only right to disobey it he is obligated to do so?

Thomas Jefferson
If a law is unjust a man is not only right to disobey it, he is obligated to do so. — Thomas Jefferson.

What conditions make a law unjust?

An unjust law is a code that a majority inflicts on a minority that is not binding on itself. This is difference made legal. On the other hand a just law is a code that a majority compels a minority to follow that it is willing to follow itself.

Should you break the law if you truly believe it?

A person must break the law not because it is convenient to do so, but because they sincerely believe the law is unjust. Finally, they must be willing to take the consequences of breaking the law. If you truly believe the law is wrong, you should break it in a public way so that people can see what you are doing.

Is it okay to violate the law if you think it’s unjust?

Probably not (because it’s difficult to prove intent). But King, Mandella, Gandhi and various other people have violated unjust laws. So I guess it depends on your definition of “okay”. The short answer is no,, no matter how unjust you think the law.

Is it possible to break the law and still be acquitted?

That includes adherence or rejection of law. It is possible, in the US, to break a law, be brought to trial, and still be acquitted, but only if the jury feels the law is bad, in which case it can be removed from the books, or nullified. From Civil Disobedience, courtesy of Henry David Thoreau (1817-1862):

Can it be morally right to break an immoral law?

It can be morally right to break an immoral law, although of course one must accept the consequences of breaking the law.