In People v. Garcia, the defendant appealed his conviction on multiple charges arising from a domestic assault episode that included stomping on some poor kids’ pet goldfish.

Judge James Catterson’s opinion explored the intriguing legal question of whether goldfish qualify as “animal companions” under statutes imposing enhanced felony penalties for abusing such companions.

The opinion started with an interesting history of animal domestication:

The earliest known domestic animal appears to be the dog, a companion to mankind as early as 15,000 B.C. Goats, sheep, pigs and cows followed in domestication in the next ten thousand years. Horses, however, did not succumb to the lure of mankind’s presence until 4000 B.C. The domestication of fish is believed to have begun much later, in China during the Tang Dynasty, around 620 A.D. The common goldfish (Carassius Auratus), a member of the carp family that was first domesticated in China, is now the most commonly kept aquarium fish. The goldfish’s leap from domesticated fish to family pet and companion may have happened as early as 1368 during the Ming Dynasty. The goldfish’s popularity in the West began as the first public aquarium opened in London in 1853. Keeping goldfish as companions and pets in the United States has been popular since that time.

 The criminal statute at issue defined “companion animal” as any dog or cat or “other domesticated animal normally maintained in or near the household of the owner or person who cares for such other domesticated animal.” The defendant argued that goldfish don’t qualify.

Here’s a healthy excerpt of Judge Catterson’s terse, well-reasoned analysis of the issue:

The defendant contends that a fish is not a companion animal because it is not domesticated and because there is no reciprocity or mutuality of feeling between a fish and its owner, such as there is between a dog or a cat and its owner.

[The defendant cites to Am. Jur. 2d, which] defines “domesticated animals” as those that “no longer possess the disposition or inclination to escape,” and claims that “if dropped in a pond and offered the opportunity to swim away, a goldfish will do so without any hesitation and not look back”. He maintains that the statute’s reference to “any other” domesticated animal limits “companion animals” to those that are similar to dogs or cats, that is, those with a degree of sentience sufficiently elevated to enable them to enter into a relationship of mutual affection with a human being. Furthermore, “[b]eloved household pets (fish) may be, but ‘companion animals’ in the same vein as dogs or cats they are not”.

The defendant’s contention that all household pets are equal but some are more equal than others is manifestly not derived from the statute. The Legislature simply did not require a reciprocity of affection in the definition of “companion animal.” To the contrary, the statutory language is consistent with the People’s contention that “domesticated” is commonly understood to mean “to adapt (an animal or plant) to life in intimate association with and to the advantage of humans”. Thus, a goldfish such as the one herein is a domesticated rather than a wild animal within the common meaning of the term. Moreover, the goldfish was, as the statute requires, “normally maintained in or near the household of the owner or person who cares for [them].” Indeed, acknowledging that the goldfish is one of the most common household pets, defense counsel stipulated at trial that there are “millions of fish owners throughout the country”.

The defendant’s argument that goldfish are not domesticated animals because given the opportunity they would leave home is without merit. While this trait arguably distinguishes fish from dogs and, probably to a lesser extent cats, it fails to take into account that many other animals commonly considered pets, such as hermit crabs, gerbils, hamsters, guinea pigs and rabbits, would depart for less confining venues and greener pastures if given the opportunity. Loyalty, if that is what it is, is merely another characteristic urged by defendant-but not included by the Legislature-as a defining feature of a companion animal.

Moreover, [the statute] provides that “[n]othing contained in this section shall be construed to prohibit or interfere in any way with anyone lawfully engaged in hunting, trapping, or fishing ….” (emphasis added). This provision would be superfluous if a fish could not be considered a companion animal.

— People v. Garcia, 29 A.D.3d 255, 257, 260–61 (N.Y. App. Div. 2006). Thanks to Dan Green.