@ Kozmik: Shamu for President!
Only those with a lifespan of at least 35 years, of course.
Or would we adjust to dog years for Fido?
I for one welcome our new testudine masters.
Well, the animal president would have to take the swearing in, which non-speaking animals can’t do. Maybe a sign-language gorilla… Koko for prez!
Koko is inexperienced!
Morla the Ancient One in 2012! 
If we ever have a mute human elected president, I doubt he would be removed for not being able to speak the oath. So that isn’t even a question.
Nobody would own animals either. You could also get a court order for the police to kick pest animals off your land for trespass. You could have them arrested for criminal property damage and such. Think of all the indecent exposure cases, and all those registered sex offender animals out there.
I am not sure that they were considered “persons” per se, but in medieval times animals were sometimes made to stand trial for crimes and even executed (sometimes by hanging).
From here:
…
Didn’t Nero make his horse a senator?
I have just realized that I have three shamefully naked cats standing at my window, exposing themselves to the neighbors. One is actually licking his nipples.
Somebody noted that if life begins at conception, and given that the 14th amendment states that citizens are persons born or naturalized in the US, and that no green cards have been issued to fetuses, then all fetuses in the US are undocumented aliens!
That was Caligula.
Unless Koko’s middle name is Hussein. That could be a problem.
And it was apparently a joke on Caligula’s part. The Master Speaks.
There are two main methods for gaining citizenship. Through birth or through naturalization. Let’s start with the easy one:
NATURALIZATION:
INA § 316(a) lists the requirements for naturalization. The animal must live within the US for five years prior to applying. This is certainly doable for many critters, but might be troublesome for mayflies. Second, the animal must not leave the US during the application period. Third, the animal must be a “person of good moral character.” Now setting aside the “person” problem, we still have the issue of whether the animal has good moral character. “Good moral character” is defined by exception in INA §101(f): you can’t be a “habitual drunkard” (§101(f)(1)), a bookmaker (§101(f)(4)), a perjurer (§101(f)(6)), or a Nazi (§101(f)(9)). Considering that it is a rare animal that drinks, gambles, lies on the stand, or invades Czechoslovakia, I think we’re good on that count.
The second set of requirements for naturalization is codified in INA § 312, which specifies that the candidate must demonstrate “an understanding of the English language” (§312(a)(1)) and “a knowledge and understanding of the fundamentals of the history […] of the United States.” (§312(a)(2). Now don’t fret, because there’s a waiver of both the literacy requirement and the civics test requirement in §312(b)(1) for people with “mental impairment.” I think being an animal is exactly the type of impairment the legislators mean here.
So it looks like we can naturalize our animals as long as we can get them in for five years on a valid immigrant visa. The two major types of immigrant visas are family (§203(a)), and employment (§203(b)). Since most animals do not have citizen family members (and it is the rare citizen who will agree to marry an animal), we should probably focus on employment visas. Here you’ll run into trouble because before you can issue a 2nd or 3rd preference employment visa (the only two types applicable here), you’ll need to get labor certification from the Department of Labor, including an assurance that this worker won’t drive down wages. Since most animals, if they work, will work for feed, you’ll have to do some fancy talking with the DOL guys.
BIRTH:
What about animals that are born overseas, you ask? Well, if one of the parents is an American citizen (Boston terrier?) and the other is not (Irish Setter?), then the American parent must have lived in the US for five years, at least two of which were after the age of 14 (§301(g)). This is going to be a pretty severe limit on most species.
For animals born here, however, American immigration law is quite famous for §301(a): automatic citizenship for “a person born in the United States” (even if your mother wasn’t allowed to be here in the first place). But that leaves us with the pesky “person” language. What does that mean? Well, according to INA § 101(b)(3), the term “person” means “an individual or an organization” but only with respect to the immigration Title, not the citizenship title, so not much help there.
Well, you CAN get naturalization in:
1, 2, 3: All good.
As for understanding english: A sign-languge chimp understands english. A dog understands some english (sit, roll over). And as for working… I can always pay my goat 8 dollars an hour, then use the money as feed.
So does that mean the coypu/nutria has no hope of becoming a naturalized citizen?
Yes please! We need more mute politicians.
I don’t know what you get, but I get asked (rather rudely, I might add) to never return to that particular zoo.