682 LAWS OF MARYLAND. [CH. 316

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 deter-
mine 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, he may forthwith 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 pro-
ducing any books or papers or doucments in any investiga-
tion or inquiry by or upon any hearing before the Commis-
sion 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 re-
quired 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 a Commissioner or its inspector or exam-
iner, testified to or produced documentary evidence of;
provided, however, that no parson so testifying shall be
exempt from prosecution or punishment for any perjury
committed by him in his testimony.

15D. In order to facilitate the making of investigations
by the State Aviation Commission, in the interest of the
public safety and the promotion of aeronautics, the public
interest requires and it is therefore provided that the re-
ports of investigations or hearings, or any part thereof, or
any testimony given thereat, shallot be admitted in evi-
dence or used for any purpose in any suit, action, or pro-
ceeding growing out of any matter referred to in said inves-
tigation, hearings, or report thereof, except in case of crim-
inal or other proceedings instituted by or in behalf of the
Commission under the provisions of this Act, nor shall any
Commissioner or employee of the State Aviation Commis-
sion be required to testify to any facts ascertained in, or
information gained by reason of, his official capacity, and,
further, no Commissioner or employee of the State Avia-
tion Commission shall be required to testify as an expert
witness in any suit, action, or proceeding involving any
aircraft.

15E. It shall be the duty of the Commission, its mem-
bers and employees, and every county and municipal officer