Casting a measured gaze on a shameful chapter of Australian history, ''Rabbit-Proof Fence'' makes no bones about who is right and wrong in its devastating portrayal of that country's disgraceful treatment of its Aborginal population for much of the last century. Although the movie, adapted from a book by Doris Pilkington Garimara, pushes emotional buttons and simplifies its true story to give it the clean narrative sweep of an extended folk ballad, it never goes dramatically overboard.

On the side of right are the Australian Aborigines whose families were torn apart by a government policy of forcibly removing children of mixed race from their Outback communities and transporting them to settlement camps hundreds of miles away. Once in the camps, they were forbidden to speak their native language and were indoctrinated into the religion and customs of the dominant white culture. Eventually they were integrated into the general population as domestic servants and farm laborers.

On the side of wrong is the Australian government, which, for more than half a century (from 1905 to 1971) carried out this appalling program of legalized kidnapping. ''Rabbit-Proof Fence'' is set in 1931, when the executor of that policy was A. O. Neville (Kenneth Branagh), a man so intransigently certain of its ultimate benefit to everyone involved that he makes Rudyard Kipling seem benign.

The chief protector of Aborigines in Western Australia in 1931 when malignant racial theories were in ascendancy throughout the world, Neville is the legal guardian of all Aboriginal people in that state. Convinced that the Aborigines are dying out, he is committed to hastening their disappearance by enforcing a law that forbids children of mixed marriages to marry full-blooded Aborigines. In one scene, Neville smugly pulls out a chart that supposedly proves how, in three generations after an interracial marriage, all Aboriginal characteristics have disappeared in the offspring.

Christine Olsen's subtle but biting screenplay and Mr. Branagh's understated performance refrain from portraying Neville as an overtly fiendish monster. As he executes decisions that are all taken in a spirit of benign paternalism, he comes across as the apotheosis of the kind of blind racism that takes for granted the superiority of white Western culture.

This sturdy, touching movie, directed by Phillip Noyce, who also oversaw ''The Quiet American,'' personalizes this historical outrage by telling the story of three young girls who escape from a settlement and set out to make the 1,200-mile trek back home on foot. The events are based on the experiences of Ms. Garimara's mother, Molly (Everlyn Sampi), who is 14 at the time of the movie; her 8-year-old sister Daisy (Tianna Sansbury), and their 10-year-old cousin Gracie (Laura Monaghan). All three are mixed-race children fathered by itinerant white fence workers.

The story begins in the tiny depot of Jigalog in northwestern Australia on the edge of the Gibson Desert. Coursing through this Aboriginal community is a rabbit-proof fence. Built to keep the country's rabbits on one side and its pasture land on the other, it spans the entire length of Australia from north to south.

Hearing that the three girls are running wild in Jigalog, Neville authorizes their removal to the Moore River Native Settlement 1,200 miles away. But when his deputy, Constable Riggs (Jason Clarke), drives to Jigalog to pick them up, he must overcome the resistance of the girls' mothers from whose arms they are forcibly wrested. The Moore Settlement resembles a spartan rural orphanage with dormitory housing and strict regimentation. When children try to escape, they are retrieved by Moodoo (David Gulpilil), an experienced black tracker, and punished with solitary confinement.

For Molly, who bridles at the daily humiliation, the final straw comes when the girls are told they have no mothers. One day while the other children are in church, she coaxes Daisy and Gracie to flee with her into the woods. The bulk of the movie follows them on a three-month trek through forest, field and desert, during much of which they use the rabbit-proof fence to guide them home. As the news of their remarkable elusiveness reaches Jigalog, Molly and Daisy's mother, Maude (Ningali Lawford), and their grandmother, Frinda (Myarn Lawford), hold a vigil in which they chant and send signals by tapping on the fence.

If ''Rabbit-Proof Fence,'' which opens today in Manhattan and Los Angeles, has the upbeat tone and deliberate pace of a ballad, Molly is its radiant folk heroine. Profoundly intuitive, indomitably courageous, endowed with superhuman resilience, she is the stuff of legend. And as played by Ms. Sampi, she emits a steady glow even in moments of desperation.

The story could easily have been treated as a brutally suspenseful manhunt in which the girls survive any number of narrow escapes from their pursuers. But in Mr. Noyce's hands their journey is touched with enchantment, and the movie becomes a paean to the beauty of the Australian countryside and the decency of most of the common people who aid the fugitives.

Under Molly's resourceful guidance, the girls are able to find enough food and water to keep them going. If their continued well-being seems unreal, that's part of the movie's myth-making strategy. As the story jumps back and forth between their journey and the frustrated attempts to capture them, at moments it almost feels like a jaunty game of hide and seek.

But the spic-and-span wholesomeness of ''Rabbit-Proof Fence'' ultimately makes its sting all the sharper. Its portrait of people who see themselves as decent, self-righteously trying to eradicate another culture, has the impact of a swift, hard slap in the face.

''Rabbit-Proof Fence'' is rated PG (Parental guidance suggested). Its scenes of kidnapping could upset young children.

RABBIT-PROOF FENCE

Directed by Phillip Noyce; written by Christine Olsen, based on the book by Doris Pilkington Garimara; director of photography, Christopher Doyle; edited by John Scott and Veronika Jenet; music by Peter Gabriel; production designer, Roger Ford; produced by Mr. Noyce, Ms. Olsen and John Winter; released by Miramax Films. Running time: 95 minutes. This film is rated PG.

WITH: Everlyn Sampi (Molly), Tianna Sansbury (Daisy), Laura Monaghan (Gracie), David Gulpilil (Moodoo), Ningali Lawford (Molly's mother), Myarn Lawford (Molly's grandmother), Deborah Mailman (Mavis), Jason Clarke (Constable Riggs) and Kenneth Branagh (Mr. Neville).

Published: 11 - 29 - 2002 , Late Edition - Final , Section E , Column 5 , Page 8