In his latest youth-obsessed head trip, director Gus Van Sant addresses that age-old question: Would Crime and Punishment have been a better read with more skateboarding in it? Paranoid Park is based on a young-adult novel by Blake Nelson that offered a riff on Dostoevsky’s classic. Of course, I don’t for a moment mean to suggest this particular appeal to youth culture represents the full scope of the filmmaker’s contemplation. On the contrary, Van Sant seems committed to the proposition that lots of moody slo-mo interludes would have improved the classic story, too.

Much of the movie’s cast of non-actors was recruited through MySpace. Among them is a wide-eyed, tousled cipher named Gabe Nevins. He plays Alex, a 17-year-old in Portland, Oregon, who has grown prematurely benumbed to existence. His parents are in the midst of a divorce. His cheerleader girlfriend is getting on his nerves. School is a dull grind he wanders through in a trance.

Only once do we observe Alex in a state approximating happiness and engagement with his environment, and this is when he visits the eponymous skateboard park on a fateful Saturday night. As he explains in voice-over, the allure of the place has less to do with riding his board (his skills aren’t quite there yet) than with the affinity he feels for the “train hoppers, guitar punks, skate drunks and throwaway kids” who illegally built the graffiti-dappled amphitheater under the concrete belly of a bridge.

It is not clear what attracts Alex to this milieu. His social circle is composed of bright, upper-middle-class, reasonably well-adjusted kids, and he comes off as far too hobbled by inertia to fancy a walk on the wild side. This is only the first of numerous paradoxes that Van Sant might help us solve, if only the filmmaker weren’t quite so preoccupied with his technique.

In the course of Alex’s evening at Paranoid Park, a grisly accident results in the death of a railroad-yard watchman. The young man certainly did not mean to commit murder. At the same time, he undoubtedly initiated the sequence of events that led to the guard being bisected by a passing train.

Ostensibly, the film’s primary focus is the moral wrestling match that follows — Alex’s struggle to come to terms with his actions. But I’ll be honest: I wasn’t convinced anything that meaningful or deep was going on here. When one of Alex’s friends mentions that simply writing about something you’ve done can make you feel better, the boy decides to put the whole terrible business down on paper. It’s not a confession, though — just a self-help exercise.

No, Crimes and Misdemeanors this isn’t. Van Sant is interested in morality infinitely less than in mood. He’s so busy fussing over dreamlike soundscapes and montages in which boarders hover above the Earth like baggy-jeaned angels that he leaves gaping plot holes in the story. For example, a homicide detective (Daniel Liu) visits with the school’s skaters to find out whether any of them were at the park on the night of the crime. He tells the kids police know someone struck the security guard with a skateboard before he died, then threw it into the river. The authorities have supposedly retrieved this board, which bears the deceased’s DNA. But, inexplicably, the detective doesn’t simply produce the board and ask the kids to name its owner. Half the students in the room would have recognized it as Alex’s. End of story.

Instead: scene after scene of Nevins walking the high school hallways in slo mo. Instead: Alex penning his account — the movie’s framing device — and fracturing and flip-flopping the narrative as if he’s just taken a course in Alejandro González Iñárritu appreciation. Instead: a hypnotic soundtrack that strings together everything from Nino Rota and thrash metal to Elliott Smith and Beethoven. Instead: montage after montage of airborne skateboarders shot in both Super-8 and 35-millimeter and at various film speeds. Larry Clark meets Warren Miller.

Paranoid Park has been hailed as Van Sant’s finest film, and it certainly does have its knowing moments and nice touches. But it seems to me the chief triumph here is one of style over substance. The disaffected kids who shuffle through Van Sant’s universe have nothing to say, nothing to tell us. I’m not sure the movie has a whole lot more.