A 13-year-old girl came to me and said she is being severely physically abused and told me about personal family problems. I explained that I cannot offer treatment to anyone under the age of 18 without parental consent, and that I am obliged to report suspected child abuse to the state department of child welfare services. The student feels betrayed. What - if anything - should I do next?
You don't indicate whether or not you're a professional counselor or, if you are, what kind. If you are a counselor, your question points to the need for a disclosure statement no matter where you are employed. Counselors who work in agencies typically have printed statements which outline with whom they can work and their responsibilities to their clients. School counselors either have printed disclosure statements or talk with students about the limits to their confidentiality before working with them individually.
Now that you know about the abuse you must inform your local child protective services office. The safety of this child comes first. You can keep confidential all of the other information the child shared with you. If you are not allowed to provide treatment to an underage client, suggest that the girl ask her parents for consent for treatment or offer to meet with them with her to ask for consent. If your call to protective services has irreparably damaged your relationship with this girl, help her with a referral to another counselor in your community.
There are many professional codes of ethics offered by different professional counseling groups for their members/certificants. You may want to check the American Counseling Association, and the National Board for Certified Counselors websites, for answers to questions about counselor ethics.