So what? You just need to come up with a policy that biases in one way or the other and does so in a way that is the most beneficial.
Look at the criminal justice system. You can't always prove guilt or innocence in many trials, many times there are cases that sit on the fence but our system is set up with the assumption of innocence.
Look at the criminal justice system. You can't always prove guilt or innocence in many trials, many times there are cases that sit on the fence but our system is set up with the assumption of innocence.