The Massachusetts Clinicians Affidavit As To Competency And Treatment is a document used by clinicians in the state of Massachusetts to assess a patient's mental competency and authorize treatment. The affidavit serves as a legal document to provide evidence that the clinician has determined a patient's mental capacity to make decisions and has provided the necessary treatments. There are two types of Massachusetts Clinicians Affidavit As To Competency And Treatment: the Competency Evaluation Affidavit and the Treatment Authorization Affidavit. The Competency Evaluation Affidavit is used to assess a patient's mental capacity to make decisions and is typically completed by a doctor or mental health professional. The Treatment Authorization Affidavit is used to authorize treatment for a patient and is typically completed by the patient's clinician. Both affidavits must be signed by the clinician and the patient in order to be valid.