Does anyone know where the police hide tracking devices on your car?

Hi I'm in CA. I have a nosy cop brother who is a megalomaniac and I would not be surprised if there's on on my car. If there is one on my car, does there need to probable cause, if it came from the police and how often do you need to change the batteries.Does anyone know where the police hide tracking devices on your car?If your car has GPS in it-you can be tracked, period. We have a store called Spy Shop You can buy bugs a nd bug finders, etc. You could probably rent something to help at a shop like that.Does anyone know where the police hide tracking devices on your car?the battery's can last a long time years they will be where ever a guy can reach usually magnetic. if your car is a old one no computer they are easy to get rid of go to scrap yard where they have a big magnet have them power up magnet while your auto is parked close to it this should fry all newer tracking devices do not try this if your car has a computer