A Dcotor bills medicare for an HP he performs but dates it the day before when the er called him but he did not see the patient and also bills for the visit that day?

That is called double billing, and it is Medicare fraud. It is against the law for any medical provider to bill for something with the wrong date of service, and especially to bill the same charge twice when it was only performed once. There is a VERY LARGE penalty for Medicare fraud. A call needs to be made to the local Medicare or Social Security office.