NICS Reporting Improvement Act of 2013 - Amends federal firearms provisions to define a person who has been adjudicated mentally incompetent or who has been committed to a psychiatric hospital as a person who is the subject of an order or finding issued by a court, board, commission, or other adjudicative body (after a hearing of which the person received actual notice and at which the person had an opportunity to participate with counsel) that found that the person, as a result of marked subnormal intelligence, mental impairment, or mental illness: (1) was an imminent danger to himself or others, (2) was guilty but mentally ill in a criminal case, (3) was not guilty in a criminal case by reason of insanity or mental disease or defect, (4) was incompetent to stand trial in a criminal case, (5) was not guilty only by reason of lack of mental responsibility under the Uniform Code of Military Justice, (6) required involuntary inpatient treatment by a psychiatric hospital, (7) required involuntary outpatient treatment by a psychiatric hospital based on a finding that the person was an imminent danger to himself or others, or (8) required involuntary commitment to a psychiatric hospital for any reason, including drug use. Excludes: (1) a person who is in a psychiatric hospital for observation or due to a voluntary admission, and (2) an order or finding that has expired, that has been set aside or expunged, or that is no longer applicable.
Defines "psychiatric hospital" to include a mental health facility, mental hospital, sanitarium, psychiatric facility, and any other facility that provides diagnoses by licensed professionals of mental retardation or mental illness, including a psychiatric ward in a general hospital.
Prohibits: (1) the sale or other disposition of a firearm or ammunition to any person knowing or having reasonable cause to believe that such person has been adjudicated mentally incompetent (currently, mental defective) or has been committed to a psychiatric hospital (currently, to any mental institution); and (2) the shipment, transport, or possession in interstate or foreign commerce of a firearm or ammunition by, or the receipt of a firearm or ammunition which has been shipped or transported in such commerce by, any such person.
Makes conforming amendments to the NICS Improvement Amendments Act of 2007.