This year’s annual compromise candidate between Sundance and Cannes’s otherwise divergent definitions of a festival film, “Fruitvale Station” is a clean-scrubbed tragedy that aims for a commendable reversal: taking a real-life human subject best known for the way he died, Ryan Coogler’s debut feature instead builds its drama around the way he lived. 

At least, it purports to do so. In Coogler’s angry but unremittingly adoring portrait, how close you feel to Oscar Grant, the 22-year-old Bay Area proletarian whose life was cut unaccountably short by a brute transit officer on New Year’s Day in 2009, may depend on how much truth you see in its tidily condensed life-in-a-day structure. And that, unlike the incontestable video-phone footage of Grant’s death that Coogler unspools as early as the prologue, is strictly in the eye of the beholder. It is one thing to present us with an atrocity that we know, and possibly even remember, happened. It is another to make us believe it.

With everything in the film but the climactic assault on the eponymous station platform shot in bright, even, comfortingly televisual primaries by cinematographer Rachel Morrison, “Fruitvale Station” has no surprises up its laundered sleeve – its brutal denouement is also its beginning, its very reason for being. Faced with that dramatic restriction, Coogler instead preys on our short-term consciousness by cultivating a sunny, honeyed tone for the bulk of his film”s necessarily brief running time, painting a protagonist so charmed – and charming – that we”re reluctant to believe he could also be so ill-fated. It”s as relentlessly feel-good a feel-bad movie as any in recent memory, but in directing those feelings to the victim rather than the crime, “Fruitvale Station” winds up telling a smaller, easier story than it could do.

Rightly or wrongly, it”s not the kind of story you”d instinctively fashion as a star vehicle, though it”s on that level that the film most unreservedly scores. Michael B. Jordan, who already announced himself as one to watch with his turn a teenage drug pusher in “The Wire,” has easily enough loose-limbed, bright-eyed charisma to bear the weight of the camera”s devoted gaze as it follows him through one scene after another constructed to demonstrate Grant”s unimpeachable niceness as he goes about his day. (On the evidence of this week’s releases alone, he may be a more natural movie star than his “Wire” co-star Idris Elba.)

Practically Jimmy Stewart in a beanie, though with more laddish, no-sweat sex appeal than that image might suggest, Jordan plays Grant as a figure whose individual magnetism is accented by his fierce sense of community, whether he”s strutting the streets while out on the lash or tenderly scaling himself to the doll”s-house world of his doting young daughter Tatiana (Ariana Neal).

He”s an irresistible enough screen presence that I wished Coogler”s thinly episodic script would challenge our inevitable response to him a little more, instead of redundantly stacking the deck in his favor as he racks up the selfless brownie points. He calls his mom on her birthday! Repeatedly! He lends his hard-up sister money, despite being hard-up himself! Repeatedly! He helps out strangers in the supermarket with recipe suggestions! He cradles dying dogs on the sidewalk! He leads impromptu unifying dance parties on crowded trains! He has weaknesses too, but none that Coogler is willing to enact: there are vague allusions to a spell in prison, though we”re never told the cause, while past infidelities to his lovingly weary girlfriend Sophina (Melonie Diaz, in a flintily sympathetic performance) are brushed aside in an incontrovertible past tense.

If I sound facetious at this point, it”s because the film”s strenuous sanctification of its working-class hero doesn”t just flatten the drama: it massages the moral stakes of the injustice at hand. Are we being encouraged to feel angrier about Oscar Grant”s senseless death because he was such a stand-up guy? Would “Fruitvale Station” be a less worthwhile cri de coeur if he”d been a profoundly flawed wastrel? And if Coogler doesn”t believe so, why is his narrative so smoothly, inorganically shaped – right down to cute chance encounters on the fateful train – to make such an agreeable martyr of its protagonist? Many will respond to the film as a gut-level human interest piece, but it”s as curtailed and nuance-free a character study as it is a political polemic.

Perhaps tellingly, the most vividly affecting sequence of the film is Coogler”s urgent, uncluttered restaging of the Fruitvale Station attack, wherein Jordan finally, genuinely bristles in response to the brash, brainless bullying of his eventual killers (played with thankless effectiveness by Chad Michael Murray and Kevin Durand). It”s the first scene in which neither Grant nor the audience can be protected with his force-of-nature personality, and it promises a necessary snap in the film”s storytelling approach, as the personal, social and legal fallout of the events demands to be mapped without the benevolent warmth of the victim”s presence.

But the promise is never fulfilled. “Fruitvale Station” stops (I wouldn”t say ‘ends”) just where I was keen for it to begin. Relegating the scandalous official consequences — which saw the offending officer, Johannes Mehserle, convicted merely of involuntary manslaughter — and ugly, community-rupturing aftermath of Oscar Grant”s death to a few tasteful title cards, the film pulls its punches so as not to misshape its neat 24-hour study of an ultimately unexamined life, and sidelines the more resonant story in the process.

We are, at least, left sharing in the tears of Grant”s mother, who – as played by the customarily wonderful and subtly skeptical Octavia Spencer, folding creases into the script from thin air – evidently knows and loves her boy”s foibles as intimately as she does his virtues. It”s more than this superficially well-intentioned but finally phony film can claim, but even that”s not quite the point. “Why do bad things happen to good people?” Coogler asks throughout with plaintive sincerity, ducking the simpler, more vital, but yet-to-be-answered question. Why did this bad thing happen to anyone at all?