A police cruiser is a good place to have a religious symbol. It could have a good influence on the unlawful who ride in the cruiser. They could ask what the symbol stands for. It might make them change their way of life.
A courthouse is the best place for the Ten Commandments. The lawless are taken there to be tried. They could their way of life is wrong.
There are so many terrible things going on in the world; you have to be very forgetful and very picky to let a religious symbol disturb you.