§ 10.   Indictment or information--Modification or abolishment of grand jury. No person shall be held for a criminal offense unless on the presentment or indictment of a grand jury, or information of the public prosecutor, except in cases of impeachment, in cases cognizable by county courts, by justices of the peace, and in cases arising in the army and navy, or in the militia when in actual service in time of war or public danger: provided, that the grand jury may be modified or abolished by law.