Once the police find my sister will they arrest her husband?

Not necessarily. The purpose of the warrant is to protect a family member from harm. The warrant does not give the police any extra powers of arrest than they already have. In order to arrest her husband the police would have to be satisfied that a criminal offence had been committed.

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WARNING: The contents of these FAQs are intended as general legal information only.
If you have a personal problem, please consult a lawyer.