I would recommend against that. My understanding of the law says that is "battery".
Far more would be achieved if they could be humiliated in a non racial way. Anything smacking of racism will do far more harm then good. It will be picked up by the national news services and turned into a club to beat opponents of illegal immigration.
Whatever is done, it would be better to be funny and completely avoid racism or even any such whiff.
Try to stop them and they will find a way to call it battery. How would that be racist? Oh yeah, the fire hoses. Well then spray them and let them beg for the fire hoses. It’s not racism and besides, they will call it that anyway.
Your approach smacks of the turn the other cheek, be nice and smile when they get in your face. How did that work out for Bush and the GOP all of these years. There is nothing funny about any of this, never was.
They understand in your face tactics and as long as we play nice with them they will continue to kick us, knowing there are no repercussions for them.