Under Law

If you don't speak the language, can you respond to the cop?

If you don't speak the language, can you be interrogated?

If you don't speak the language, how much justice can you expect at the trial? You have to rely on a great translation of everything your lawer, the judge, the other lawyer, and the witnesses say. Imagine if the big item which proves the witness is a liar wasn't translated (for brevity) or mistranslated?

How can you plead for clemency or pardon from an executive branch official if you don't speak the language?