The zombie film lends itself well to allegory. “Night of the Living Dead” is about civil rights. “Dawn of the Dead” is about consumerism. Even “Diary of the Dead”, however clumsily it articulates the idea, is about the information age. “I always used the zombie as a character for satire or a political criticism”, George A. Romero reflected in a recent interview, “and I find that missing in what’s happening now.” He was referring in particular to AMC’s “The Walking Dead”, a series whose cadaverous masses have been thoroughly drained of signification, but the charge could be leveled at any number of trivial exponents of the zeitgeist, from “Warm Bodies” to “World War Z”. It isn’t simply that zombies used to mean something — it’s that the very appeal of zombies lay in their capacity for meaning. The zombie, with its lifeless pliancy, can stand in for anything, readily taking on whatever meaning is implied by its context. Romero conceived of zombies as empty vessels, enemies lacking even a pretense of emotion or psychology. They are the ultimate Other: a threat that means both nothing and everything.

In 1976, eight years after the release of “Night of the Living Dead” and two before “Dawn”, John Carpenter was inspired to make a film that loosely followed the George Romero template, drawing a line from the heaving faceless masses of “Night” back to the prison-siege framework of Howard Hawks’s “Rio Bravo”. It proved a thoughtful connection. The resulting film, “Assault on Precinct 13”, plays out in the intersection of its two seemingly incompatible influences — a Western without the West, a zombie film without zombies. The connection to Hawks is obvious enough: as in “Rio Bravo”, a local man of law must protect the prisoners who are his temporary charge against a band of armed outsiders wanting in. The difference is that, unlike in its predecessor, the villains in this case aren’t interested in anything like a prison break; here revenge is the only catalyst for the siege. But the connection to Romero is more complicated. There a few apparent similarities — a solitary location held in lockdown, a need for barricades and defense, a (pointedly) black lead — but what Carpenter borrowed is even more basic. He borrowed the zombies.

Now, this parallel has been observed before, but it nevertheless requires a little context to properly illustrate. For one thing, it’s important that the film doesn’t so much follow a plot as it does arrange its players like pieces on a board: on one side there’s Lieutenant Ethan Bishop (Austin Stoker), a rookie cop assigned to preside over a relocated precinct’s last night in operation alongside its two remaining secretaries, Julie (Nancy Loomis) and Leigh (Laurie Zimmer). Meanwhile, Special Officer Starker (Charles Cyphers) finds himself in need of a nearby holding cell when the prisoners he is escorting by bus to death row, Napoleon Wilson (Darwin Joston), Wells (Tony Burton), and Caudell (Peter Frankland), claim that one among them has taken ill. The two groups converge and attempt to summon a police doctor by phone in the otherwise abandoned station. A few blocks away, a man (Martin West) finds his daughter (Kim Richards) shot dead at random by a gang of local hoodlums. Firing back and killing one of them, the man flees, charging into District 13 in a state of shock. Once the film has conspired to bring these elements together under one roof, the development of story more or less stops dead. All that remains is the fallout: our wily band of heroes must endeavor to hold off the raid.

The characters mentioned above, of course, are people — well-realized, three-dimensional people, with individual desires and motivations. Their aggressors, by contrast, are very much anonymous: they are given no names, no dialogue, no identifying features. They form a nebulous, threatening mass, a storm front of nobodies, each member inseparable from the group. They can’t be calmed, persuaded, or otherwise reasoned with. They are unthinking and ceaseless, always marching ahead, sometimes directly into gunfire. In other words, they are zombies — they function identically, distinguishable from Romero’s lot only for the simple and largely cosmetic reason that they are not especially corpse-like to look at them. Well, does it really matter if they’re breathing and running about? The key thing about zombies, in Romero’s estimation, is that they are empty enough to contain some other urgent meaning — they need to function, en masse, as a vehicle for ideas. And Carpenter’s pass this test.

Indeed, they may serve this use a little too well. “Assault on Precinct 13” is a film that, for all its simplicity and elegance of form, is often misinterpreted. This mistake is not unreasonable. The film’s zombies, such as they are, come to be associated with the wayward members of the Los Angeles underclass — prone to mindless violence, unthinking in all actions, and essentially immoral. The film’s heroes, meanwhile, come to be associated with the valiant members of the Los Angeles police department, from its noble impromptu deputies to its overnight administrative staff. An obvious reading therefore presents itself: state force is L.A.’s last and best line of defense against the ghetto’s seething, inchoate poor, who will doubtless rise up and violently revolt at the slightest provocation. It makes the film seem practically fascistic. But in practice that isn’t quite the film’s agenda.

It’s true that “Assault on Precinct 13” makes a threat of the working class, but it’s important to remember the aggression which informs them: the film opens, not insignificantly, with an unprompted raid by police on a relatively benign Los Angeles ghetto. Our introduction to the world of this film is the slaughter of a dozen men for what appears to be no reason by SWAT team armed with shotguns. The police have set the precedent of violence; the gangs we see thereafter are acting in retaliation. And their zombification by Carpenter, therefore, is a gesture of sympathy — not for the gangs and not for the police, but for anybody would gets wrapped up in this cycle of pointless violence. Carpenter conceives of a figurative ‘zombie apocalypse’ as triggered by the brutality of the police: and the fallout is death and destruction on both sides of the battle. Bishop himself, you’ll recall, makes a point of explaining that nobody picked him out of the ghetto when he was a baby — he walked out himself at twenty, and he turned out okay. Our hero isn’t “the police” as an institution, but rather a man who bridges the two sides, a man from one world trying to do the right thing in other. This is what makes “Assault on Precinct 13” such an exemplary zombie movie: like Romero’s best films, it uses the form as a vehicle for political criticism.

“Assault on Precinct 13” is now available on Blu-ray from Shout! Factory.