For starters, the “assault weapons” ban of 1994 had no meaningful effect on the homicide rate.

Congress reconvenes this week after a summer fraught with multiple mass shootings. Reportedly, legislation implementing tighter gun control is on the table, with rumored support by some in the White House. The rhetoric surrounding guns continues to escalate.

Here’s the thing about guns. The Constitution—that handy little document—guarantees our rights to them, and that guarantee is a profound reflection of the nature and character of our freedoms. As Ben Domenech of The Federalist wrote recently, “the right to bear arms is not about hunting.” Rather:

It is a natural right of the deepest significance to the relationship between the citizen and the state. It is in the Constitution because the men who defeated the greatest empire in the world wanted us to be able to defend our freedom.

The simple fact that we have a right to own guns doesn’t mean individuals must own them, use them, or even like them. But what it does mean is that people advocating further regulation of firearms at least should have a baseline understanding of how firearms actually work, as well as the current statutory environment that regulates their purchase, handling, and use.

Unfortunately, the current rhetoric coming from Democrats betrays a deep misunderstanding about all of those things.

Here are some of the worst offenses.

Bernie Sanders: “We must end the sale and distribution of assault weapons.”

There’s a lot to unpack here about so-called “assault weapons.” The first challenge is the absence of any fixed legal definition of what constitutes an “assault weapon.” Numerous state laws have defined the phrase as everything from paintball guns to all semiautomatic firearms to Remington 11-87 shotguns, the latter famously used by former presidential candidate John Kerry (D-Mass.) on Labor Day in 2004 to demonstrate his legitimately good trap-shooting skills.

The vague term “assault weapon” is distinct from an assault rifle, however, which refers to a rapid-fire, magazine fed rifle that allows the shooter to select between semiautomatic (requiring you to pull the trigger for each shot), fully automatic (hold the trigger and the gun continuously fires) or three-round-burst modes. Assault rifles are, for all intents and purposes, already banned in the United States. More on that shortly.

So for anyone proposing to ban “assault weapons,” the question needs to be: which guns? Because, depending on your definition, it could be just slide action shotguns and guns with adjustable stocks, or it could be every semiautomatic pistol in America as well as your kid’s BB gun.

Dianne Feinstein: “The assault weapons ban worked. Studies prove that mass shootings dropped while it was in effect.”

Except it didn’t. “There is no compelling evidence that it saved lives,” according to Duke University public policy experts Philip Cook and Kristin Goss. A 2004 Department of Justice study found no evidence the ban had any effect on gun violence, stating “should it be renewed, the ban’s effects on gun violence are likely to be small at best and perhaps too small for reliable measurement.” Other studies have found no statistically significant relationship between “assault” weapons or large-capacity magazine bans and homicide rates.

There is also substantial misunderstanding surrounding what the Assault Weapons Ban, which passed in 1994 and sunset in 2004, actually did. It didn’t ban anyone from owning an “assault-style” (again, an undefined term) weapon. All magazines and weapons produced before the ban were grandfathered in, and some companies actually ramped up production of the soon-to-be-outlawed firearm components, drastically increasing ownership of what lawmakers were seeking to reduce.

So if the ban didn’t actually apply specifically to types of guns, to what did it apply? Mostly cosmetic “military-style” features. Specifically: semiautomatic rifles with detachable magazines and certain additional features, including pistol grips, bayonet mounts, folding stocks, or magazines holding more than 10 rounds of ammunition.

Also, given the frequently cited claim that “assault weapons lead to more murder,” it’s worth pointing out that at least 730,000 AR-15s (not an assault rifle, but more on that in a bit) were manufactured and legally sold while the Assault Weapons Ban was in effect, and the national murder rate declined.

It’s also true that rifles like the AR-15 are only used in a tiny percentage of murders. Twenty-seven percent of murders are committed without firearms of any type.

Beto O’Rourke: “Americans who own AR-15s, AK-47s, will have to sell them to the government.”

Ah, yes, the mandatory “buyback.” O’Rourke gets so much wrong here. First among them, as Matt Walsh has pointed out, is the concept of the “back” in “buyback.” That assumes that Americans would be returning their guns to the original owner, which is . . . the government? Uh, no.

It’s also a misnomer to say that the government would be “buying” anything. That suggests choice, when this is very much a mandate. Moreover, the government would be “buying” guns from legal gun owners and reimbursing them with their own tax dollars.

In Walsh’s phrasing, “a mandatory buyback” is like calling armed robbery “a compelled donation.”

Experts who have studied gun buyback programs done at the state level say they are largely ineffective at reducing crime rates or gun violence. In the words of one expert, the impact of buybacks on crime was “not statistically significant.” In other words, buybacks are good for photo ops and for when you’re trying to jumpstart a foundering presidential campaign. But they don’t actually get crime off the streets.

Kamala Harris: “As president, I will take executive action to . . . ban the importation of AR-15-style assault weapons.”

Some things to clear up here. “AR” does not stand for “assault rifle.” An AR-15 is not, in fact, an assault rifle, because it only fires one round with each pull of the trigger. (Again, there is no fixed legal definition for “assault weapon.”)

An AR-15 is classified as a modern sporting rifle, used for hunting, competition shooting, and home-defense, and one of the most popular firearms being sold today—upwards of 16 million Americans own them. Even with that many purchases, AR-15s and similar sporting rifles still comprise only 3 percent of the total civilian arsenal of approximately 310 million firearms.

AR-15s are legal to own in most states, provided that the purchaser passes the mandatory FBI background check required for all retail firearm purchases.

Oh, and one more thing: The vast majority of AR-15s are manufactured in the United States. So an import ban would be meaningless.

David Axelrod: “Weapons of war kill large numbers of people . . . why are they still legal?”

Axelrod doesn’t define what he means here as “weapons of war” (no one ever really does), but this seems as good a time as any to point out the key differences between automatic weapons (largely banned) and semiautomatic weapons (mostly handguns).

An automatic weapon can shoot more than one round when you pull the trigger (e.g.: a machine gun). A semi-automatic—most handguns, many rifles, and some shotguns—does not. Contrary to popular belief, automatic weapons have not been used in recent mass shootings—semi-automatics have been.

Moreover, the only automatic weapons legal to purchase for civilians in the United States are those registered between 1934 and 1986. Since 1986, Congress has forbidden gunmakers from even producing fully automatic weapons for the civilian market. Automatic weapons have been heavily regulated since the National Firearms Act of 1934.

If you want to take possession of an automatic weapon, the bar is quite high. A substantial transfer tax, application, federal background check, and fingerprinting are all required. If you violate the Firearms Act? Good luck to you—you’ll sit in prison for 10 years and pay up to $100,000 in fines.

Chuck Schumer: The Odessa shooting “could have been avoided” with a background check bill.

Actually, no.

The Odessa, Texas shooter did not legally own his gun, an AR-15, and existing laws made it illegal for him to purchase one. He obtained his gun from a currently unidentified person that law enforcement officials believe may have illegally manufactured and sold the gun to him.

Some commentators claim the fact that the gunman bought his weapon through a “private sale” meant that he escaped a background check. But let’s be very clear here. He escaped a background check because the seller was selling illegally. Private sales require the seller to be legally compliant, and private sales also require background checks. Legal private sales are still federally regulated and there are harsh penalties for buyers and sellers who violate the law.

The shooter was also prohibited under federal law from owning a firearm because a court previously had found him mentally unfit. He evidently had tried to purchase a gun in January 2014 but failed because the nationwide criminal background check system had flagged the mental health determination.

The federal Firearms Transaction Record, form 4437, required for all gun purchases, asks “have you ever been adjudicated as a mental defective or have you ever been committed to a mental institution?” Falsifying the form is a crime.

It was later revealed the shooter had a criminal record that included pleading guilty to criminal trespassing and evading arrest, both of which are misdemeanors in Texas. He did not receive jail time, but instead got two years of probation.

The Odessa shooting was a horror. But existing laws prevented it from happening sooner. And the fact that he got a gun at all tells us what common sense already teaches: motivated criminals don’t abide by laws.

As my boss, former U.S. Senator Jim DeMint (R-S.C.) said recently, the breakdown of the culture is more responsible for mass shootings than the availability of the guns themselves. There are myriad reasons for this, but lawmakers, he noted, need to set a better example for how to treat people before rushing to strip Second Amendment rights from the rest of us.