Can you face stiffer penalties from the court if your blood alcohol concentration is found to be higher than 0.10?

It depends on the state, some yes. But it looks a lot better when you are in front of the judge because remember he can give you the minimum fine/sentence or the most he has that call so the less it is most of the time it is the judge will not give it to you as bad as if it was high even if you did not hit anyone or anything.