If you suspect your daughter is abusing drugs or alcohol, you likely want to take action. But assuming an authoritarian approach in making demands of your daughter will most likely not be fruitful. Arguing with your daughter or making accusations will not force her into getting the treatment she needs.
A better approach is to express your concerns for your daughter based on the evidence that she is abusing alcohol or drugs. For instance, if your daughter is missing school or her grades are dropping, and you’ve noticed that she has seems the little disoriented at times, mention this to her. If you have concrete evidence that she is abusing alcohol or drugs. present that to her.