While the document in question still exists, it is not currently being used and does not appear to be accessible through the city's website.
The only ordinance I see a problem with is 123.02
123.02 AUTHORITY IN A CIVIL EMERGENCY.
(a) Whenever the Mayor determines that an emergency exists as a result of any natural disaster or man-made calamity, or clear and present danger thereof, or riot, insurrection, mob action or other civil disturbance causing danger of injury or damage to persons or property, the Mayor shall have the power to impose by proclamation any or all of the following regulations necessary to restore the peace and order of the City:
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(6) Prohibit or restrict the sale, distribution, dispensing or giving away of any firearms or ammunition of any character whatsoever;
(7) Order the closing of any and all establishments or portions thereof engaged in the sale, distribution, dispensing or giving away of firearms or ammunition;
(8) Prohibit or restrict the carrying or possession on the public streets or public sidewalks or in any public park or square or any other public place a weapon or any object intended to be used as a weapon, including, but not limited to, firearms, bows and arrows, air rifles, sling shots, knives, razors, broken bottles, fire bombs, missiles of any kind, clubs, blackjacks, billies, chains or similar items;
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The only authority the mayor would have to do so is in a cordoned off area during a riot:
http://codes.ohio.gov/orc/3761.16" onclick="window.open(this.href);return false;