To judge from online comments, gun enthusiasts are frothing at the mouth over an ordinance New Orleans Mayor Mitch Landrieu seems likely to get adopted by the New Orleans City Council.

It does not take much to reduce Second Amendment zealots to that condition, and, naturally, they are greatly alarmed when Landrieu and council members claim to have a plan to reduce carnage and keep guns kept out of the wrong hands. But there’s nothing to worry about.

It is so obvious the ordinance will not have the advertised effect that we must look elsewhere for its real purpose. Far from cracking down on gun offenders, it would keep lots of them out of the jail Sheriff Marlin Gusman runs but Landrieu must find the money to pay for. It also would enable New Orleans to present a less hairy face to the world through FBI crime statistics.

This transformation would be achieved by reclassifying state gun felonies as municipal misdemeanors. This is an admirably simple expedient, but, alas, there is a catch: It is totally, patently and spectacularly illegal.

Landrieu and a couple of council members touting the ordinance are attorneys, while taxpayers fund a whole department charged with providing legal advice. There must be someone at City Hall capable of looking up the Revised Statutes, which say “no governing authority of a political subdivision shall enact an ordinance defining as an offense conduct that is defined and punishable as a felony under state law.”

New Orleans is set to do just that with this ordinance, which creates several municipal crimes punishable with a maximum $500 fine or six months in jail. One is carrying a gun in a school zone, another is possessing a gun with obliterated numbers and a third says no guns if you’ve been convicted of domestic violence. All those offenses carry five years in prison under state law.

The ordinance also bans guns from playgrounds, which is not currently against state law, so it’s OK, right? No, there’s a catch here too. Another state statute that says local government may adopt no gun ordinance “more restrictive than state law.” There is a bill pending in Baton Rouge to outlaw guns in playgrounds, but whatever happens to it, the corresponding section of the New Orleans ordinance will be illegal under one statute or another.

Two sections of the ordinance do appear to be legal, but our joy in that is not unalloyed because neither does a lick of good. One would criminalize the “negligent carrying of an concealed firearm” and is a straight lift from the statute book. Negligent carrying would be a misdemeanor, punishable by up to six months in the slammer, under either code.

The state law seems never to have been enforced, although a prime opportunity arose in 2010 when a ditzy Galatoire’s diner dropped her purse, causing her pistol to discharge a bullet into the wainscot. District Attorney Leon Cannizzaro declined to file charges.

The point of wrapping a dormant state misdemeanor into the municipal code is not easy to fathom. Maybe the plan is for NOPD to start booking people with negligent carrying, passing up more serious charges. This would certainly fit in with the ordinance’s other sections, which would reduce the number of felony prosecutions reported to the FBI.

The ordinance also makes it a crime not to report the loss or theft of a firearm within 48 hours. There is no reporting requirement under state law, so the city is within its rights on this one, and maybe it will help law enforcement somewhat. Convictions will be rare, however, for proving that a loss or theft has not been reported punctually likely will be impossible unless the suspect chooses to incriminate himself.

If any city is crying out for rational gun control, it is New Orleans. But this ordinance, insofar as it has any effect at all, can only hurt that cause. It is the citizens in daily fear of gun violence who should be frothing at the mouth over this utter sham.

James Gill’s email address is jgill@theadvocate.com.