At first I thought this might be like Donkey Boy in another gender, but as we get to know the character she seems less and less alien in some dimensions.
Dancer is more a continuation of my previously reviewed film by this same director, Breaking the Waves, which focuses on a woman of unnatural innocence who gets everything fubar as a consequence.
Selma Jezkova's loyalty to secrecy and "keeping mum" is too strictly translated into her native Czech I think. She should have been more forthcoming in her own defense at the trial. "Yes, I lied my way through the eye test, I just didn't want Jessie to worry" -- which explains how the conflicted / confessing cop got to the cookie jar.
Jessie is her son and the metaphor for their blindness (both use thick glasses) is strengthened in their mutual caring mixed with alienation. They're not on the same page in a lot of ways.
That the mother feels guilt or even actual responsibility for Jessie's karma is something the court would respond to, but why not just tell it like the movie we all just saw? Spill the beans already. Relay each conversation. Having secrets means you're capable of sharing them.
The film is scary. Showing the state committing murder and the eeriness of the prison relationship... is it progressive blindness or madness, as the musicals become more hallucinatory in quality? The music comes from another time, closer to our own.
But then imagining an audience of voyeurs to one's life is like madness, but then so is a sense of being "on stage"... so then who isn't mad in that sense? The eyes of others are upon us, if not literally in a theater.
The movie twists around to ask that question. It also asserts something about the musical: the opera uses music and dance to express an underlying story that the banal plot lines of cinema verite (and real life) would not capture. The surreal mirrors the real. Art shows us other angles.
In treating serious darkness with musical numbers, the genre is fighting back against rumors of being antiquated.
The musical episode, of the Buffy series, is a another one to link in.
The women in both these movies are "too child-like for their own good" one might say. On the other hand, both are dealt a rotten hand of cards and it's easy to armchair-criticize.
These films encourage empathy, but with empathy comes a desire to coach, to offer advice. Many a sports fan knows that impulse. You feel in their corner.