Trial court did not err by failing to give a mistake of fact instruction. In his appeal from the denial of his habeas petition challenging his jury conviction for vehicle theft (Veh. Code, sec. 10851), Byrd contended that since there was evidence that the victim gave him permission to drive the car, the trial court erred when it failed to instruct sua sponte regarding mistake of fact. The appellate court disagreed, finding that the evidence demonstrated that no reasonable juror would have concluded that Byrd actually believed he had been loaned the vehicle. Scope of consent instruction improperly lowered the prosecution’s burden of proof. Byrd also challenged the trial court’s scope of consent instruction, contending that it lowered the prosecution’s burden of proof. The state court agreed, but found the error harmless. The federal appellate court reversed the district court’s denial of habeas relief. Once the state court determined that the scope of consent instruction impermissibly lowered the government’s burden of proof as to the consent element of the crime, application of harmless error review was no longer an option.