A B.C. aboriginal woman has launched a class-action lawsuit against the Correctional Service of Canada over the classification of all aboriginal women serving time in federal jails.

Tanya Lorraine Neill of the Gitxsan First Nation says she was wrongly sent to a medium security prison last year. She argues she should have been put in minimum security, as she had no previous criminal record.

Neill says all aboriginal women sent to federal jails have had the same problem, because Corrections Canada uses a rating scale that's designed for male inmates and is biased against female aboriginal inmates.

Her lawyer, John Conroy, says that overclassification on the custody rating scale means aboriginal women serve more time behind bars than other inmates.

"Of course, the higher your security classification, the more difficult it is in terms of various types of passes, in terms of parole and these sorts of things."

Conroy says federal law requires prison officials to use the least restrictive measures appropriate for an inmate.

Neill's statement of claim has been filed in the Federal Court of Canada.