When do you consent to take a blood test for alcohol content?

The correct answer indicates that by driving in California, you give implied consent to submit to a blood test if requested by law enforcement. This law is part of California's "implied consent" law, meaning that anyone operating a vehicle implicitly agrees to these tests as a condition of holding a driver’s license. If a police officer has reasonable cause to believe that you are driving under the influence, they can ask you to take a test to measure your blood alcohol content (BAC).

The other options do not accurately reflect the circumstances under which you must comply with a blood test. Merely being stopped for speeding, being involved in an accident, or having a request from another driver does not create the same legal obligation to consent to a blood test. Only law enforcement, under specific circumstances, has the authority to request this test in accordance with the implied consent law.