Mounted cops ARE useful for the reasons that several other posters have stated. Mounted cops also have, I think, a tremendous advantage in terms of goodwill. People generally like horses, or at least find them interesting. So there’s something engaging about a cop on a horse, much more so than a cop on foot or in a car.
You can’t just pull a horse off the shelf and put it in service. Horse and rider, when called into duty, have to have some degree of a symbiotic relationship. Maybe in some cities the mounted police are superfluous but in a cities like New York and New Orleans where crowd control is a predictable occurance, a mounted police force can almost be considered a necessity.
I think I read that Toledo deployed mounted cops during the recent Nazi-related violence. I was surprised they had any. Is it a city particularly prone to mob violence?
you have to see what mounted cops can do in a crowd control situation, the horses are very well trained and can be used to push crowds around without crushing toes and stuff like that.
add to that fact the intimidation+visiblility+ability to go places cars cant and you have a force that is well worth the effort, keep in mind that while they arent in heavy use in Seattle they are easy enough to call up on fairly short notice.
I have seen them perform crowd control up close and personal, its impressive what 3 guys on horses can accomplish in 10 minutes that the 30 security guys couldnt in 45 minutes…horses are friggin big. people respect that.
. . . and when was the last time you heard of a horse being overturned and set on fire by an unruly crowd?
In America, Polic Horse beats YOU! 
An Irish girl in my building was telling about attending a football match back home. After the match, everyone is shunted through a high-walled cattle chute down to the subway, where the horses act as gates. They turn 90 degrees to block the path, then turn again to let people through. Nothing like a big hulking hairy beast to stop some drunk soccer hooligans in their tracks (so she says.)
The horse cops are constantly on patrol in Times Square (for crowd control) and they always seem very calm hanging around one of the noisiest places on earth. I think they’re either deaf or just used to it. 
When I went to the balloon fiesta a couple weeks ago, there weren’t many LEOs that I saw–at least, not on the field. There were two Bernallio County sheriff deputies riding horses and an Albuquerque police officer riding a Segway. Guess which one made me nearly break out in laughter? And, frankly, I think the horse would be more useful overall than a Segway.
There are many people who would have no problems attacking or throwing things at policemen in full riot gear yet would never imagine hurting a horse. This gives mounted policemen a certain degree of protection.
Sounds like the horse confers a largely psychological advantage. Which is nothing to sniff at, of course. Better than a nightstick. It would be great if we lived in a world where cops could be armed with intimidation instead of guns,
If the police force has the horses, for the situations that have been described, the alternative would be to leave them in the stables. If it (a) involves a policeman who would otherwise be on the same streets on foot, and (b) works wonders for PR for the police, then why not?
As others have said, it’s about more than height. A line of well-trained horses is a formidable obstacle for almost any crowd - FWIW, dozens of mounted police are a normal sight at a British football match. They’ve easily manouvered, and in seconds can form a barrier in places you’d struggle to set one up otherwise. And, importantly, when not being used in this way, they don’t seem intimidating or agressive in the way a hundred riot police would do if they were lurking around waiting for action.
Police horses are trained to get used to these sounds and situations. I have seen a couple of TV programmes showing this process. They get people to line up and blow trumpets, bang drums, let off fire crackers and wave banners. After a time they become immune to it all . I think the same training is given to the army horses you see in London.
Here’s a page about London’s Metropolitan Police’s mounted unit, including training
About 12 years ago I was in England at Buckingham Palace waiting to see the changing of the guard. The crowd was kept behind those short steel barriers but had gotten too close to the end of one. This tiny little young woman on horseback asked he crowd to backup… then again… then again… nothing happened. She rolled her eyes, tapped the horses ribs and had the horse gently bulldoze 8 or 10 people several feet back - they didn’t push forward again that afternoon.
That would have taken 3 or 4 big men to do and likely resulted in insult hurling and possibly a fight without the horse. She did it in about 5 seconds all by herself.
I also had a fishing license checked once on the river. The spot I was at was about a 20 minute walk from the nearest road. No modern-day 50 year-old 280lb obese fish and wildlife officer would be justified (or want) to walk that long to end up accomplishing nothing all day. He was on horseback though, and probably looked forward to spending a week out on patrol riding a horse down the riverbank for miles and miles writing the occasional $200 ticket and enjoying the scenery and fresh air.
Mounted police haven’t outlive their usefulness quite yet…
Also, don’t discount the “animal” aspect, which also applies to police dogs. A cop is a person like you and me (I hear) so you can predict the way they are going to act. You can argue with a cop and you’ll probably just get a few bumps and bruises if you’re arrested, or you can run away, and maybe get away. Chances are you won’t get shot or wind up seriously injured. Cops are people who could get in big trouble for going overboard, so they generally keep their actions moderate. There are always exceptions, of course.
Screw with an animal, and you don’t really know what’s going to happen. That horse can step on you and you’ll need an EMS team to peel you off the pavement. That dog could tear your throat out if his partner lets go of the leash.
There is also the “I can kick that ____'s ass” concept. A drunk or a rioter may think he can knock that annoying cop out with one roundhouse. Seems like an even match. I know for a fact that I can kick a motorcycle’s ass. But a snarling dog… a HORSE? Fuggedaboutit.
You can’t argue with or fight a horse for your rights, you just stay out of the way.
Somebody mentioned police in riot gear. Don’t forget that most crowd control is not riot control, but rather parade & sporting event and concert and festival and … crowd control.
If a typical American in of a crowd at a parade and found themselves facing police in riot gear, there’d be a 100% replacement of the city council, mayors office, and police cheif within a couple of months.
Conversely, put a few cops on horseback with the same crowd and it seems almost quaint & fun, not the threat it really is.
Crowd control is a strange psychological balancing act. Decent people in a huge crowd must be treated very gingerly by the cops to avoid triggering a simmering ugliness deep in teh human psyche (and definitely enhanced by alchohol). But once ugliness starts, the cops need a firm hand to get it stopped again. While still not forgeting that most of the miscreants are not hooligans much less serious criminals; just ordinary folks caught up in the mob excitement of the moment.
That’s one of those situatiosn where a ton of prevention is worth an ounce of cure. Horses work good for prevention.
Ummm - just for clarification, have you ever been near a horse? A big 16-18 hand hunter type horse, that is?
1000lbs+ of bone and muscle is a hell of a lot more than a psychological advantage. A well-trained horse is basically a primitive Hulk suit for a policeman, with the advantage that it looks pretty innocuous when not in active use, can then go easily into semi-polite ‘push-n-shove-n-tussle’ mode as mentioned by other posters, and if necessary can go full-on ‘SMUUUSH’ at anyone who deserves it. Add in hands-free control, cross-country capability, semi-autonomous operation and all the other stuff that comes as standard on a horsie, and you have a very valuable piece of equipment - how much do you think Boeing or General Electric would charge a PD for something that useful?
As to crowd control:
I attended a Grateful Dead concert at the Cap Centre outside DC several years back and afterwards the usual milling about took place (lots of people with no place to go, jawing about the show, etc. etc. etc.). The mounted police lined up their horses nose to tail and had them walk sideways through the crowd.
A wall of horses, moving in unison will clear a crowd out of the way with amazing efficiency.
Imagine if the mounted police were issued sabres…
Just kidding! But the thought did cross my (unbalanced) mind.