VANCOUVER - A British Columbia man who plied two teenage girls with drugs and alcohol, sexually assaulted them and failed to intervene as they died is appealing his dangerous offender designation.

Martin Tremblay of Richmond was handed an indeterminate prison sentence in December for his role in the deaths of 17-year-old Martha Jackson and 16-year-old Kayla Lalonde.

Tremblay was convicted of criminal negligence causing the girls' deaths after he invited them to his home, gave them drugs and alcohol until they passed out and videotaped himself sexually assaulting them in March 2010.

The sex offender failed to help the girls when their conditions deteriorated and drove Lalonde to Burnaby, where he left her on the ground, before Jackson stopped breathing at his home the next morning.

Tremblay is appealing his sentence on the grounds the dangerous offender designation is overbroad and violates his charter rights

His appeal references the case of Donald Boutilier, where a B.C. Supreme Court Justice ruled such a provision is unconstitutional, but B.C.'s Criminal Justice Branch is appealing the ruling.