A new defence of partial provocation for victims of family violence who in turn kill or are violent to their abuser would create major problems, says the Law Society.
The Law Commission is reviewing the law and suggests a partial defence similar to manslaughter would take into account someone suffering prolonged abuse.
In a newly-published submission, the Law Society agreed there was major concern with how the law operated.
However, it warned introducing a partial defence would lead to controlling and violent partners minimising their own violence, and victims embelleshing the violence they had suffered.
It made several of its own suggestions, including a separate homicide offence, that a jury be allowed to hear evidence about family violence, or changes to self-defence.