A lot of very big guns are wheeled on to make a weirdly muffled and underwhelming bang in this stately, high-minded feature from Emilio Estevez, shot in the (impressive) location of Cincinnati public library, which incidentally gives the film the odd look of something shot by documentarist Frederick Wiseman.

The story feels as if it is based on a real incident, but it isn’t. Or rather, only in the sense that it reportedly had its genesis in a news story Estevez read 13 years ago about how American public libraries were becoming de facto daytime shelters for the homeless. He sets out to imagine what would happen if these people staged a protest about funding, and this has been a passion project Estevez has been developing since then.

Estevez himself plays Stuart, a librarian who was himself once homeless, hanging out in this very library, and saved by literature. Michael K Williams plays Jackson, one of the homeless guys who comes in there; Jeffrey Wright is Stuart’s exasperated boss Anderson. When a chaotic and unplanned sit-in evolves out of the men’s refusal to go out into the freezing temperatures one night (there are, incidentally, no women among the homeless), Stuart impulsively supports them. Alec Baldwin plays the city cop tasked with keeping this situation under control, and Christian Slater is the slimy and uncaring public official with no empathy whatsoever.

It is a film with its heart in the right place, but the dialogue and characterisation are both plonkingly unconvincing. There are repeated montages of readers coming in to ask the librarian questions – to which the honest answer, in every case, would surely be, “Try Google”, and the film only glancingly acknowledges the fact that in the online age, reference libraries must arguably redefine their existence. Estevez deserves points for taking on a relevant issue.

• The Public is released in the UK on 21 February.

•This article was amended on 19 February to correct the statement that this is Emilio Estevez’s directorial debut.