Del. Code tit. 2 § 140
The Department, any member thereof, the Secretary of Transportation, or any officer or employee of the Department designated by it may hold investigations, inquiries and hearings concerning matters covered by the provisions of this chapter and orders, rules and regulations of the Department, and concerning accidents in aeronautics within this State. All hearings so conducted shall be open to the public. The Secretary of Transportation, and every officer or employee of the Department designated by it to hold any inquiry, investigations or hearing may administer oaths and affirmations, certify to all official acts, issue subpoenas and compel the attendance and testimony of witnesses and the production of papers, books and documents. In case of failure to comply with any subpoena or order issued under authority of this chapter, the Department, or its authorized representative, may invoke the aid of any court of this State of general jurisdiction. The court may thereupon order the witness to comply with the requirements of the subpoena or order or to give evidence touching the matter in question. Any failure to obey the order of the court may be punished by the court as a contempt thereof.
2 Del. C. § 140