Dogs have a keen sense of humor, so it only makes sense they would be governed by a set of laws that are equally humorous, albeit in an ironic and twisted way.

Loosely based on Murphy’s Law for the human universe that tells us anything that can go wrong undoubtedly will, Murphy’s laws for dogs share the same clear-cut philosophy. As with any set of laws, some of the Murphy laws for dogs are broad enough to cover canines across the globe while others have regional variations that stick close to Tucson – literally. Such as the jumping cholla law.

No matter how small or carefully hidden a cactus patch may be, if one exists, the dog will find it. He will not find this aforementioned patch while sniffing softly and treading lightly, either. Said cactus patch will be found while he bolts off to chase a rabbit. The rabbit, of course, is familiar with the patch and hops merrily through the little non-needled nooks and crannies along a tiny, meandering path. The dog, of course, comes back with stickers in his tongue. The said cactus patch will be jumping cholla. The vet will inevitably be closed.

If you walk your dog in the dark and forget a poop bag, the only car of the entire night will drive by right as the dog is doing his business. If the moon is smiling mightily on you that night, that lone and only car will also happen to turn into the very driveway onto which your dog just pooed.

The forgotten-poop-bag law has a clause that actually applies to any time of day and any location. If you are the only person walking your dog across the lonely Arctic where no other human has trod for the past 27 years, one will just so happen to show up at the exact moment your dog begins to squat.

The moment you take your dog off his leash for a little romping in an open area, you will encounter one of three things: a zooming coyote, an angry St. Bernard, or an animal control officer. Not that we here in Tucson would so blatantly disobey the leash law, but just so you know three good reasons why you shouldn’t. A fourth very good reason is the $250 fine.

The moment you sit down to eat, relax, recline or lie down in bed, the dog will suddenly need to go outside. Never mind that you were just out in the backyard for the past half hour. Never mind also that you let him in and out for the past full hour. Dogs have a certain, specific sensor that alerts them you are about to eat, rest or drift off to sleep. The alert causes a loud, painful-sounding bark or an equally loud, excruciatingly annoying banging, scraping or scratching paw down the back door.

If you install new wood doors, floors or cabinets, the dog will suddenly form a new scratching habit. This particular habit is most likely to form not at your own home, but when you are either visiting a client, dog-hater or mother-in-law who said for this one time only you could bring your dog along. “He won’t be any trouble,” said you, although you’re now trying to figure out how to hide the scratch marks while your gracious host stepped briefly from the room.

New dog habits also suddenly form due to other fresh improvements around the home. A dog that barely even scratches after a pee will suddenly become a lean, mean digging machine if you plant new grass seed. A dog that never chews on anything, including his specialty rawhide, will suddenly find the need to chomp on upholstery when you get a new couch. A dog that has never jumped on anyone in his life will find that yen deep in his soul with muddy paws on a house guest wearing white.

The more money you spend on a dog toy, the less likely your dog will be to play with it. The $15 squeaky, bright purple duck toy has actually started rotting in the yard it’s been untouched for so long but you cannot wrench the cardboard the duck toy came in away from your pooch. The law, unfortunately, does not apply to costly food and treats. Dogs will typically turn their noses up at the $1.49 liver bites yet inhale a full bag of $14.99 chicken strips without even chewing.

The more you pamper your dog, the more he will expect. This is not really a law per se, but a trap into which many animal lovers fall. The pampering will start out with normal-type behaviors, such as giving your dog a good brushing or belly rub – but they will eventually morph into incredibly ridiculous behaviors like sleeping on the couch so the dog can have your bed or watching only movies for which the dog likes the soundtrack.

The sad part is many dog owners don’t realize how far down into the pampering trap we’ve fallen – until it’s much too late and we no longer have a bed or movie choices beyond bad musicals. But we do realize one more adage that will always hold firm and true: the more you love your dog, the more he will love you back.