See
BRB page 181, 4. resolve attacks 1. hit roles:
A 1 always fails, irrespective of any modifiers that may apply
page 181, 4. resolve attacks 2. wound roll:
A 1 always fails, irrespective of any modifiers that may apply
page 181, 4. resolve attacks 4. saving throw:
A 1 always fails, irrespective of any modifiers that may apply