AERONAUTICS 171

a court of equity to order the closing of any airport, or landing field, or to
order any air school, flying club, or air beacon, or other air navigation
facility to cease operations until it shall have complied with the require-
ments laid down by the Commission. To carry out the provisions of this
sub-title the State Aviation Commission and any officers, State or mu-
nicipal, charged with the duty of enforcing this sub-title, may inspect and
examine at reasonable hours any premises, and the buildings or other struc-
tures thereon, where such airports, landing fields, air school, flying clubs,
air beacons, or other air navigation facilities are operated. Any order made
by this Commission pursuant to this sub-title shall be served upon the inter-
ested person by registered mail or in person before such order shall become
effective.

An. Code, 1924, sec. 15C. 1935, ch. 316, sec. 15C.

18. The Commission or any Commissioner, or officer of the Com-
mission designated by the Commission, shall have the power to hold in-
vestigations, inquiries and hearings concerning matters covered by the
provisions of this sub-title, and all accidents in aeronautics within this
State. All hearings conducted by the Commission shall be open to the
public. Each Commissioner, and every officer of the Commission desig-
nated by it to hold any inquiry, investigation or hearing, shall have the
power to administer oaths and affirmations, certify to all official acts, issue
subpoenas, compel the attendance and testimony of witnesses, and the
production of papers, books and documents.

If a person fail to comply with any subpoena or other issue under the
authority of this sub-title, or if a person in attendance before the Com-
mission or a Commissioner refuse, without reasonable cause, to be examined
or to answer a legal and pertinent question, or to product¹ a book or paper
when ordered to do so by the Commission, the Commission or such Com-
missioner may apply to any Judge of the Supreme Bench of Baltimore
City, or of the Circuit Court of any County, upon proof by affidavit of
the fact, for a rule or order returnable in not less than two or more than
five days, directing such person to show cause before the Judge who made
the order, or any other Judge aforesaid, why he should not be committed
to jail; upon the return of such order, the Judge before whom the matter
and such person shall come on for a hearing shall examine under oath
such person and such person shall be given an opportunity to be heard;
and if the Judge shall determine that such person has refused, without
reasonable cause or legal excuse to appear before the Commission to
be examined or to answer a legal or pertinent question, or to produce
a book or paper which he was ordered to bring or product, ¹ he may forth-
with commit the offender to jail, there to remain until he submits to do the
act which he was so required to do, or is discharged according to law.

No person shall be excused from testifying or from produring¹ any
books or papers or documents in any investigation or inquiry by or upon
any hearing before the Commission or any Commissioner, when ordered
to do so by the Commission or such Commissioner upon the ground that
the testimony or evidence, books, papers or documents required of him
may tend to incriminate him or subject him to penalty or forfeiture; but
no person shall be prosecuted, punished or subjected to any penalty or
forfeiture for or on account of any act, transaction, matter or thing con-
cerning which he shall, under oath, have, by order of the Commission or

¹ Evidently a typographical error.