Which circumstance allows for a legal search of a vehicle?

The correct choice, which involves consent from the owner, is grounded in the principles of search and seizure as upheld in the Fourth Amendment of the United States Constitution. When a vehicle owner or any person with authority over the vehicle voluntarily gives consent for law enforcement to conduct a search, it removes the requirement for probable cause, reasonable suspicion, or a warrant. This consent must be informed and given freely, meaning that the owner understands their right to refuse and agrees to allow the officers to search the vehicle.

The other circumstances listed do not provide a lawful basis for searching a vehicle. Officer suspicion alone does not meet the legal threshold required for a search; there must be additional justification, such as probable cause. The presence of an attorney does not inherently grant the legal authority to search a vehicle without the owner's consent or without meeting the established legal criteria. Random chance does not qualify as a lawful reason for a search, as searches must adhere to constitutional guidelines rather than be predicated on luck or coincidence.