Looks like a member of the pig line to me???  Its not a marsupial, dog, or feline, or rodent, so WTF is it????

AZ has this to say...

Though some people think javelina are a type of wild pig, they are actually members of the peccary family, a group of hoofed mammals originating from South America.

FURTHERMORE


Laws and Policies

The department will sometimes remove javelina that are causing extensive property damage or have become aggressive toward humans. However, this is a last resort, and measures must be taken to remove attractants to prevent problems from recurring.
Javelina are classified as a big game species. It is unlawful to injure or kill game animals, even if they are causing a problem, unless certain rigorous provisions under the law have been met. See Arizona Game and Fish Department Hunting Regulations.
It is unlawful to trap javelina.
State law prohibits firing a gun within a quarter-mile of an occupied residence or building without the permission of the owner.
Check your local city ordinances, but most cities ban shooting firearms within city limits. Some cities ban the use of slingshots, BB guns, air guns, or bows.
Refer to ARS-17-239 on wildlife depredation and Arizona Game and Fish Department Hunting Regulations for more information

I told you what they were in a previous post.  here it is again. COLLARD PECCARY.

I am not trying to be obtuse here, but some folks are  saying pig, and this has implications about being a non-native pest/varmint/shoot on sight species.

Craig

Not quite.  It is not illegal to discharge a firearm within 1/4 mile of a structure. It is, however, illegal to hunt with a firearm within 1/4 mile of a structure unless you have permission to do so.

It is illegal to kill any wild animal in Arizona without a hunting license. Javalina are a managed species and require a tag. Coyotes are considered pests and can be killed all year long and you can kill as many as you like. You still need a general hunting license.

I would recommend an electric fence around your garden and put your garbage cans inside a wooden frame so the javalina can't knock them over. I would waste every coyote I could. Get a suppressor (unrestricted magazine size and suppressors are legal to hunt with in AZ)if you don't want to rile up the neighbors, then go to town on their asses. Be aware, if you shoot a hole in a neighbor's house or shed, your ass is going to jail.

So we are arguing legal definitions.  

Thanks for all your suggestions.

We have had this problem for over 5 years, but has been getting worse as of late. I have 2 poles that are concreted in the ground, and each trashcan gets tied to one, so they can't knock it over. But somehow, and I really don't know how they're doing this, they manage to get the cord untied, and knock it over - I'm going to have to bring the cans into the garage or something.

They seem to be getting more and more aggressive - I was charged by a male and had my leg gashed open a couple of years ago. I think you're right though, someone in the area is probably feeding them. They will come into our yard atleast 3 times a night. The dog will start going nuts at all hours, and we go outside and chase them off.

The bottom line is if one of these pests get anywhere near my son, they're dead. If I have to goto jail, so be it. The chihuahua that was killed was absolutely torn to shreds, it's terrifying to think of that happening to my son.

Matt,

I was simply answering your query as to WTF is it.  We can go round and round as to what it looks like, what it smells like and how it behaves, but the OP was seeking advice, and some folks were assuming
that it is a pig or "hog" type critter from their state that perhaps has less "legal" standing.  When it comes to blasting wild animals on your land, you would be well advised to understand whether that animal is
"legally" classified as a game animal.  If the law wants to push the issue, discharging a weapon could just be a ticket.  Poaching, shooting a game species out of season, could be a ticket, a large fine, siezure
of weapon or even jail time.  So you and I are talking scientific semantics,   the OP has a legal issue.

Adapt,

more than likely the javelina are being fed by lots of folks, with their trash cans.  If they are coming in at night, and keying on your cans, most likley they are adapting (sorry) to their new food source, the trash can circuit.  
Around here we have been in a drought for the last decade or so, and most of the critters have been changing their habits.   Hopefully removing the trash will cause them to not hit your place so frequently, or at all.  At my last house,
the trash was a losing battle with the bears.  And I did not even know we had racoons around here, until I found several sleeping in my trash can bottom.  You might also do a little research on them to see about removing
any natural food source from your yard, if able.  But they eat some pretty nasty prikly stuff, so maybe you have already gotten rid of that, due to the kids ;^)  And if you want to find out how they are coming in, and have a little fun, game
cameras are pretty cheap these days.  Good luck,

Craig

Not hardly. The javelina is also known as the collared peccary, named for the white band, or collar, that runs across the shoulders. Contrary to popular myths, javelina are not members of the rodent family, nor are they actually members of the pig family (although many hunters commonly refer to them as pigs). Their characteristics are unique enough to place them in a separate family with two other species of peccary: the white-lipped and the Chacoan.

Much maligned for their lack of intelligence, the javelina is not any less intelligent than our other native wildlife. They simply developed a different combination of attributes to survive in their environment. Their eyesight is very poor at distances greater than 100 yards. This is understandable for an animal that evolved in the thick brush, where food, water, shelter and predators could only be seen at very short distances. Their sense of smell and hearing abilities, however, are very well developed.