It sounds you really did something wrong. But sometimes some of police twist what you say to them expecially you are a Chinese. They will, any how, make you a criminal as long as they do not like you. Don't trust too much on police, they are cookers. Chen Min case is a good example. They don't have enough evidence and arrested him. Even they say today they find finger prints same, they still can not say he is the criminal. I say this since I do not like the way that police treat Chinese. This is an example of racial profile.
If you were video taped you still have a Chance to exclude it as evidence by appling Chater 14. It depends on Judge. But if you commited you are most likely convicted.
In your case, go back China and never come back again or find a lawyer to fight for you.
Regarding to the Charter, this is Canadian Charter of Rights and Freedom. But US and Canada both inheritated the law from British law, and Canada has more laws from French law. But Charter is most similar.