One of the nice things about America is that if you wish to do such for a funeral of one your deaceased loved ones you can.
Well, at least America used to be that way. More and more the Nanny-staters wish to impose their will on the rest of us. Especially it seems when a time honored tradition of repsect and honor is on the line. (Like putting up a cross in memory of deceased soldiers and such...)
My father, grandfather, and uncle were all law enforcement of various types. Everyone of them hated the processions because of the danger involved in them. Neither my father nor my grandfather had a procession at their funeral.