Philadelphia and Pittsburgh Mayors Jim Kenney and Bill Peduto recently coauthored an op-ed explaining why they oppose Pennsylvania Senate Bill 531 (SB 531), which prohibits local governments from regulating firearms.

SB 531 shouldn’t be necessary. It largely reiterates the Pennsylvania Uniform Firearms Act, which itself reiterates Article I, Section 21 of the Pennsylvania Constitution, which in turn, reiterates the Second Amendment of the United States Constitution. How many times and in how many forms does a law have to be enacted to be accepted by the political class?

Mayors Kenney and Peduto call for “commonsense” gun laws, but what they want is nothing of the kind. Many gun owners would and do welcome commonsense legislation. A recent Pew poll found that almost 90 percent of both Republicans and Democrats agree that people with mental illnesses should be prevented from buying guns. More than 80 percent of both Republicans and Democrats agree that people on no-fly or watch lists should be barred from buying guns. And these opinions aren’t driven by people who have no experience with firearms. More than 70 percent of polled Americans have fired a gun at some point, and almost half grew up in a household with guns. There is actually tremendous agreement on what reasonable people would call “commonsense regulations.” That politicians like Mayors Kenney and Peduto see things differently is telling.

The mayors cast themselves as protectors of the people, saying that Philadelphia and Pittsburgh have “no choice but to pass and enforce laws that protect our residents.” But common sense would admit that guns can be used defensively as well as offensively, and when police are minutes away, making it harder for citizens to use guns defensively achieves the exact opposite outcome the mayors claim to seek.

A 2013 report on gun violence commissioned by the Centers for Disease Control and Prevention concluded that defensive gun use by victims ranges from 100,000 to 3 million instances per year. By comparison, there were around 11,000 murders by firearm in the U.S. in 2017. Even if the study’s most conservative estimate overestimated the defensive use of firearms by a factor of 10, it’s still the case that defensive gun uses equal or outnumber murders. By the numbers, making it harder for law-abiding citizens to obtain guns could easily result in more deaths, not fewer. Common sense would not ignore this possibility.

Common sense would also require that proposed gun laws have some meaningful effect. And this is where so many efforts at gun control lose the support of reasonable people. In response to the Tree of Life synagogue shooting, Mayor Peduto recently signed a gun-control ordinance that bans a variety of weapons in Pittsburgh. But, had it been in place at the time, this ordinance would have done precisely nothing to prevent that shooting. Without checkpoints and searches at the city’s limits, anyone who wants to bring a banned gun into Pittsburgh need merely do so. The new regulation makes for great public relations, but for improving safety, it makes no sense at all.

One might argue that doing something — anything — at least makes a statement. If “anything” could be done without cost, and if “anything” did not make people less safe, one might have a point. But laws are costly to pass. Drumming up support for new legislation costs political capital. Researching, writing, and communicating proposed laws costs financial capital. And there’s the opportunity cost of diverting the machine of government away from other important concerns. If, as data on defensive gun use suggest, the “anything” actually makes people less safe, then doing nothing might be far better than doing “anything.”

Common sense says that the mayors are wasting our time and resources railing against a proposed law that reiterates an established law, which reiterates the Pennsylvania Constitution, which reiterates the United States Constitution. If the mayors truly want a solution that reflects common sense, they should begin by treating gun violence as the mental-health issue common sense says it is, rather than the gun issue political sense says plays to their party’s base.

But abandoning political sense for common sense is foreign to most politicians even in the best of times. And now, with election season on the horizon, we can expect politicians to be talking about what’s good for the voters while peddling what’s good for themselves. To expect better from them is simply not common sense.

Antony Davies is associate professor of economics at Duquesne University. James R. Harrigan teaches in the department of Political Economy and Moral Science at the University of Arizona. They host the weekly podcast, Words & Numbers.