Md. Code, Agriculture § 10–707

No person may be prosecuted for violation of any provision of this subtitle where it can be established that the fruit or vegetable passed inspection by an authorized inspector of the Department or by an inspector of the United States Department of Agriculture and was graded, packed and marked in accordance with the provisions of this subtitle. Certificates of inspection issued by any of these inspectors shall be accepted as prima facie evidence of the facts contained in them.