Yes, always a brilliant move to risk a trial, where anything can happen (trouble locating witnesses, inconsistent statements, evidence being suppressed, a simply terrible jury, a simply awful prosecutor, a simply incompetent judge, a great defense attorney, a procedural error, a clerical error, an expert - in this case an accident reconstructionist - who gets his lunch handed to him, a mens-rea argument that negates some, or all, elements pertaining to intent, a causation argument that decimates the actus-rea element.... shall I go on???) and to ditch a plea offer, because you don't like them. I'm sure that you are likely a huge fan of costly, untimely,and unpredictable trials though, right? Fortunately, most DA's have a little bit better grasp on the cost benefit analysis that's inherent in the decision to try or not to try a case. I don't always agree with many prosecutors, but if ideas like yours were the alternative, and allowed to permeate the system, we'd be in an awful mess.