One of the things I remember from my undergraduate psyche courses is that “insanity” is a legal term and “psychiatry” is a medical discipline. Doctors can thus describe an individual’s mental condition in clinical terms, but it’s up to a judge or jury to determine whether that person is insane.

Because I’m neither qualified nor inclined to probe the murky depths of psychiatric literature to render a proper diagnosis of the most recent accused mass murderer, this time in Colorado, I’ll suggest that he fits the profile of a common — if informal — police classification: The doer was obviously “bat-shit crazy.”

This discouraging assessment is not meant to mitigate his criminal culpability. His reported actions before, during and immediately after the incident clearly indicate that he knew what he was doing and understood that society would disprove of his bloody agenda. But people who dress up like the Joker to shoot random strangers in the audience of a Batman movie are probably not tuned in to the same frequency as the rest of us.

That said, I will argue that the best and surest outcome for the (alleged) offender is a speedy trial followed by a swift trip to the death chamber. The supposedly humane alternative — life imprisonment without parole — leaves jailers, medical staff and comparatively innocent fellow inmates to deal with this clown for decades to come. A quick death spares everyone involved a socially awkward situation.

Happily, it is not my job to determine the accused psycho’s fate. The courts will act under the rule of law. What is worth discussing, however, is what can be done to prevent similarly deranged individuals from staging an encore of senseless slaughter. In absolute terms, the answer to that is simple: nothing.

There are currently more guns in the United States than there are adults to shoot them. Given that fact and the chronic problem of mental illness, some guns are bound to wind up in the hands of nuts. Though future tragedies are a sure bet, we might want to consider ways to limit their happenstance.

It is presently against federal law for convicted felons and people who have been adjudged as mentally incompetent to purchase or possess firearms. Before you can buy a gun from any American firearms retailer, the FBI has to run a computer check through the National Crime Information Center files to ensure that you’re not a felon. Of course, the NCIC has no way of judging your current mental state because it’s not illegal to suffer from mental disease.

Restrictions on gun purchases vary from state to state but have generally been relaxed in recent years. Missouri law reflects that metamorphosis.

Prior to 2004, a person who wanted to purchase a handgun here had to apply for a permit from his county sheriff. The fee for application was a non-refundable $10. The exact make, model and serial number of the weapon had to be specified, as did the identities of the proposed buyer and seller.

The sheriff then had 10 days to approve or deny the application. During that interim, he ran the same NCIC inquiry that the FBI now does, along with state and local record checks to catch scrapes with the law that did not necessarily result in felony convictions.

The sheriff could also interview references listed on the form, along with neighbors, associates and the applicant himself. If the permit was denied, the applicant was entitled to a hearing in the Equity Division of the Circuit Court to appeal the decision. The sheriff’s office maintained records of all completed transactions.

The system was not foolproof and undoubtedly imposed a burden on the buyer. It also granted the sheriff a measure of subjective discretion that was not always used wisely. One former lawman, for instance, was notorious for denying applications from married women because he was afraid they’d use the guns to shoot their husbands.

Today, a gun shop customer simply selects the weapon(s) he wishes to purchase and shows a photo ID to the dealer who then calls a dedicated phone line to run the required record check. The buyer also completes a multi-paged federal form that, among other things, asks the individual if he’s mentally incompetent. All honest crazy people are eliminated at that point.

Unfortunately, most psychos think they’re alright, and it’s the world that’s screwed up. And although the form details the federal laws one would violate by lying on it, those prohibitions are unlikely to deter an aspiring Joker plotting mass murder.

Further, it is left to the retailer to determine whether the ID presented is valid and whether the person depicted on it is the actual buyer. The seller, of course, doesn’t make any money unless the sale goes through.

The accused killer in Colorado — where gun purchase procedures are similar to Missouri’s — was able to buy two Glock pistols, an assault rifle and a pump-action .12 gauge shotgun between May 22 and July 7 this of this year. He raised no red flags in any of these four transactions.

Of course, in those cases, the gun dealer profited while the buyer left the premises with an unloaded weapon. When the suspect tried to join a shooting club — where he’d be handling fully loaded firearms — he met with a different fate.

After reviewing his completed application, the club owner called the applicant’s phone number to discuss the matter. After listening to the outgoing message on the disturbed young man’s voicemail, the owner promptly rejected his request for membership and ordered his staff to bar him from the premises.

If this person had to apply for a permit from his local sheriff before each of his purchases, somebody might have noticed that he was compiling an arsenal. Such oversight could help to keep lethal instrumentalities — at the very least handguns and assault rifles — from persons who should never own them.

Assigning this duty to local authorities would avoid a further expansion of federal bureaucracy, and the additional expense to the concerned agencies could be defrayed through appropriate application fees.

Admittedly, introducing a disinterested referee into the transaction would make it more difficult for legitimate shooting enthusiasts to buy certain guns. That seems a small price to pay, however, because the status quo leaves all of us at the mercy of the Joker.