The officer is required to provide a clear explanation as to why they believe a search is necessary. That being said, they could hypothetically reason that if they are seizing the vehicle due to the driver's inability to operate it without a license, an inventory search of the vehicle is necessary. This would ensure everything is accurately recorded to shield the police from potential allegations, such as the theft of a significant amount, like $1000, from the backseat. Courts have confirmed that such inventory searches are legal.