The “Protect and Serve Act,” now pending in both the House and Senate, would essentially turn assaulting a police officer into a federal hate crime. This has been a long-time hobbyhorse of Republicans, including Attorney General Jeff Sessions. Any way you want to look at it, it’s a terrible idea.

The bill is response to a problem that doesn’t exist — the alleged “war on cops.” For most of its supporters, the bill is incredibly hypocritical, in that it creates a federal crime from behavior that is more than adequately addressed at the state and local levels. And, if passed, the bill could cause real harm by deterring real victims of police abuse from filing complaints. More on that later.

The conventional thinking on hate crimes is that, when someone kills or assaults or commits a property crime like vandalism in such a way that targets the victim because they are a member of a vulnerable community, all members of that community are affected. The problem with adding police officers (or the military — another group some Republicans have tried to add) is that they are about as far removed from a vulnerable group as one can imagine. They carry guns and other weapons. They have the power to detain, arrest, and kill. And they literally have the entire government at their backs. That’s who they represent.

The argument for these kinds of laws is that there’s a “war on cops,” and that laws such as this one are needed to protect them. This is nonsense. As we’ve discussed on this site many times over, both killings of and assaults of police officers have been in decline for 25 years, with some spikes and dips along the way. (So far this year, killings of cops are about 25 percent higher than last year at this time, though 2017 was one of the lowest years on record.) The only real change the public’s relationship with the police of late is that there is more skepticism, accountability and protest of police brutality. Cellphone video is providing a narrative which, in many cases, contradicts that of the police. Publications such as The Post are creating databases of people killed by law enforcement. And groups such as Black Lives Matter are raising awareness about police brutality. This is all being done without a corresponding increase in violence against police. This is a healthy thing in a democracy; it ought to be celebrated. Instead, it’s cast as a “war,” to which lawmakers then respond with this type of legislation.

As Monique Judge pointed out at The Root, it isn’t as if assault on police officers goes unaddressed. I’d venture to say that if you go out and kill, maim or injure a police officer — particularly if you do so as part of some stated anti-cop ideology — there isn’t a district attorney in America who wouldn’t charge you to the fullest extent of the law. Support grew for hate-crimes laws because there were parts of the country where assaults against people of certain ethnicities, races or sexual orientations weren’t taken seriously by local authorities. I can’t imagine there’s a place in the country where this is true of law enforcement.

What harm could come of this bill? An assault on a police officer charge is often used a cudgel — it’s a way of dissuading legitimate victims of police brutality from filing complaints. If such an assault charge could soon come with an additional federal charge punishable by up to 10 years in prison, that cudgel grows by about 10 sizes. It gets awfully persuasive.

Or think about a demonstration where police push into a protest line, resulting in pushing and shoving. It would now get pretty easy to start handing out assault charges against the protesters. A politically ambitious U.S. attorney who wants to, say, shut down Black Lives Matter could get a lot of mileage out of this bill. If you’re skeptical, look at the case of Rakem Balogun, who is among the first people targeted in the FBI’s pursuit of so-called “black identity extremists.” Balogun was put under surveillance because of anti-police messages posted to Facebook, his advocacy of gun rights for black people and his presence at anti-police-brutality rallies. He was held in jail for five months without bail on a single charge that was later dropped.

This bill is also an assault on federalism, which is unfortunate given that most of its co-sponsors would claim to be federalists. For starters, as noted, it’s not as if state and local authorities aren’t already prosecuting people who assault police officers. But let’s go back to that protest scenario. Picture a protest at which things get out of hand, and skirmishes break out between police and protesters. It isn’t clear from cellphone video and interviews with people at the protest if the police or protesters are at fault, so the local district attorney doesn’t press charges. Or perhaps it’s just a more reform-minded district attorney who thinks charges may chill the right to speech and protest. It isn’t at all difficult to picture a conservative U.S. attorney swooping in with federal assault charges.

Lately, we’ve recently seen a few instances in which district attorneys or grand juries have declined to charge the targets of drug raids who shot at police as they tried to batter down a door. In a couple of other cases, a jury has acquitted someone on such charges. Two of these cases were in Texas, a state with a strong Castle Doctrine law and an appreciation for the right to defend one’s home. Again, it isn’t difficult to see a U.S. attorney using this law to bring a second round of charges in such cases, despite the fact that the cases were handled in accordance with local laws, customs and values.

The politicians pushing this bill point to ambush-style killings of police officers, as if those somehow emphasize the necessity of creating this new federal law. But no ambush killing of a police officer goes punished — or at least no such crime for which the assailant is known and is alive. At best, this bill allows someone to be charged and convicted in both state and federal court for the same crime.

In the end, the bill is either redundant or it provides a way for a federal prosecutor to charge someone for an act that a local prosecutor or jury has determined wasn’t criminal.

The House bill was introduced by Rep. John Rutherford, a first-term Republican from Florida and former sheriff and sheriff’s deputy in Jacksonville; and Rep. Val Demings (D-Fla.), an African American and the former police chief of Orlando. The Senate version was introduced by Rep. Orrin G. Hatch (R-Utah), and Sen. Heidi Heitkamp (D-N.D.). Heitkamp seems like the most interesting co-sponsor. She’s a red-state Democrat facing a tough reelection in November. By signing on, she gets to look both tough on crime and pro-law enforcement without the worry of alienating the communities this sort of bill will most likely be used against.