You would have a potential grounds to sue because of the emotional trauma to you and your family for the temporary loss of your daughter.  In these types of situations, you basically sue everyone in the chain:  hospitial, testing facility, person who drew the blood, the person who tested the blood, the CPS worker, the sheriff.  Your challenge will be suing the CPS worker and the sheriff.  For whatever reason, CPS workers have basically been given carte blanche to rip kids away from parents on any assumption they make with very little consquences because they have what is called governmental immunity.  However, visit with an attorney that specializes in suing governmental entities to see what remedies are available to overcome that immunity.