If the police discover evidence of child abuse, the case would be referred to the DA's office to review and determine whether child abuse charges should be filed against the stepmom. Depending on the specific facts, they could be misdemeanors or felonies.
She can be arrested, charged with crimes; as could the father if he knows of the abuse and is permitting it to happen without taking any corrective or protective actions. Also the kids could sue the step mom in civil court for monetary damages.
We have dad and step-mom. Where is Mom in this mess? If this is in court [dependency] all parties, including Mom, should have an attoreny. Otherwise , there really isn't enough facts here to offer much of an opinion
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