Sure, every dog park has guidelines--pick up the crap; don't leave your dog unattended--stuff like that. But these relatively minor constraints don't address the more subtle problems one can encounter while letting Rover frolic.
1. If you're a raving lunatic, you're not allowed in the dog park. A woman sitting on the bench beside me was crying because a mean guy had told her she shouldn't come to the dog park anymore. He told her nobody liked her. I was shocked. What a cruel thing to say!
Then this poor woman--wearing three plastic hospital bracelets, which should have tipped me off--proceeded to show me the scar on her neck from when a serial killer tried to murder her and told me that both her mutts were rescue dogs that had been nearly beaten to death with baseball bats. One of them reportedly had to have his ears sewed back on. She went on to regale me with the details of some disgusting intestinal procedure she'd undergone at the local hospital due to her chronic bloody stools. She would have kept it up forever, but I was saved when a 3-year-old asked if she could pet one of the woman's dogs. Upon being given the go-ahead, the kid was regaled with the exact same stories. Having notified the kid's dad, I went back and told that woman she shouldn't come to the dog park anymore, since nobody liked her.
2. No pit bulls. I'm sorry. I know this rule is going to stir up a lot of flak. I have nothing against pit bulls personally, despite having had to beat one silly with a two-by-four years ago to free my shepherd mix from its jaws. The truth is, most are fine with people, and the ones guilty of eating children are usually the result of crankhead dumbshit owners. This doesn't alter the fact that the breed was developed with one purpose, and one purpose only: to successfully fight and kill other dogs. Most dogs' default settings are different: fetching dead ducks, for example, or herding sheep. Most dogs behave pretty well at the dog park, but once in a while, spats do occur, and when a pit bull goes off, it can kill or maim another dog before anyone even realizes there's a problem.
3. Which brings me to another problematic dog breed: Great Danes. Granted, these are almost universally gentle giants, but some of us own brain-dead herding dogs that mistake Great Danes for cattle, and we get yelled at by their owners since our dogs won't stop harassing them. This causes unnecessary stress. This may be an unfair and arbitrary rule, but since I'm making them up, I'm entitled. So please, if you're at the dog park, and your Great Dane is being mercilessly harassed by a deranged heeler mix, go home.
4. No calling your mutt from the pound a "rescue dog." I've noticed a disturbing trend lately. It seems as though everyone who gets a dog either at the pound or the Humane Society calls their dog a "rescue dog." This is a subtle shift in language usage--like Realtors calling houses "homes"--insidiously making its way into the culture. Just because you only want to pay $80 for a dog instead of hundreds to a breeder, it does not make you Mother bloody Teresa. If you want to be a hero, go find a well and pull a toddler out of it, or jump into an icy river and rescue a submerged driver.
5. And finally, for your own health and safety, never stand in one place too long at the dog park. In case you haven't noticed, there aren't a lot of trees in Tucson, and there's nary a fire hydrant in any dog park we've visited. Dogs, God bless 'em, will make do with what's available.
You have been warned.