You probably should hire a family lawyer. Of course the simplest easiest solution was to take the drug test since as you state there was no basis and you would have passed. Fighting with DCF for principals sake is a sure lose lose proposition. You will now need to hire a lawyer.
Providing general answers are meant to help the poster to understand some complex legal concepts and in no way creates an attorney-client relationship.
They may not be able to force you to take a drug test, but your refusal does not mean they have to dismiss the abuse claim. If you qualify you may want to discuss this situation with a local legal aid attorney.
This answer does not establish an attorney client relationship, nor does it constitute specific legal advice.
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