Re the interpreter who demanded an interpreter story, can you not see that in the heat of the moment, where you might be experiencing considerable stress, you may find that you cannot think as quickly or accurately in your non-native tongue? It is perfectly possibly that the guy was working the system but better that than a miscarriage of Justice.
It is also difficult for family to be impartial. For example, my mother is English speaking and is blooming awkward about everything. The other day she was speaking about going back on a medication which is highly addictive and makes her even more vulnerable. I might be tempted to interpret that she doesn't want that particular medication if I could get away with it because it will make everybody's life of those caring for her, absolutely hellish. I'm not the type of person to do that because I believe that, as hard as it is to cope with, she has the right to make up her own mind but others may not see things in the same way.