RoRo: "When thieves are doing naughty things how do the policemen know? How does he know
who to put in jail? How does he know if he doesn't see them ... if he's at home or in an office?"
Eldest: "I know! I know! He has a Blue Box!"
Eldest: "The policeman has a blue box at home and it rings like a telephone."
RoRo: "Like the Tardis?"
Eldest: "No, it's smaller. It rings and it prints off pieces of paper to tell him what to do."
RoRo: "Oh, OK."
This is part of @actuallymummy #wotsofunee linky