What happens when a driver claims no alcohol, but officers detect a strong odor masked by hand sanitizer? How do field tests reveal impairment after a long work shift? >> An insurance card. >> Huh? >> The reason why I asked as I'm standing here, I could smell the alcohol coming from the car. Okay. How much did you have to drink today? >> I want to drink. No, I'm I want to show you like the garden from I'm going to drink. >> Okay. All right. Look at this light. >> Okay. You see this little light right here? >> Yes. >> Okay. Look at this light. Follow this light >> with your eyes and don't move your head. Okay. Okay. >> No. >> Okay. Watch the light. >> Okay. >> Okay. >> But you're going to have to you're going to have to wait. >> Okay. >> Put your right foot in front. Where's your right foot? >> Look, pick up your foot like this. You're going to look at your feet. You're going to look at your foot and you're going to count. 1 10 100 >> 2 1 100 3 100 4 100 Count straight. Straight leg. >> Turn around for a second. Look that way. Turn around. Look that way. I'm going to be transporting one in vehicle 906. Starting mileage 7134.8. >> Transporting one for 450. Starting mile 7134.8. 02 01 at the time. Your your car is being towed. >> After failing standardized field tests and a breath sample reading 0.11, she was arrested for DUI and processed at headquarters. What role does masking odor play in these stops? >> Going to a toy yard. >> What? Impound yours.