Like many Americans, I spent the last week or so thinking often about the massacre of 19 young kids at an elementary school in Uvalde, Texas. Two teachers were also killed, and the husband of one of those teachers suffered a fatal heart attack a few days later, leaving their four children without parents. The community’s grief is, by all accounts, overwhelming. And even in a country that’s grown somewhat inured to mass shootings, this one stood out.

In the days since the tragedy, what we’ve learned about the shooting and the police response to it looms as something even more disturbing. Though officials initially said a school police officer exchanged fire with the body-armor-wearing gunman when he arrived on campus, they later admitted that no such confrontation happened and that the gunman wasn’t wearing body armor. When officers did arrive on the scene, state officials acknowledged to reporters late last week, they did not confront the gunman until nearly 90 minutes after the murders began. News outlets reported on Tuesday that the local police department and its school counterpart are no longer cooperating with state investigators.

In the most immediate sense, that decision raises a host of questions. Could more lives have been saved if police had interceded more swiftly? Why did officers on the ground ignore training that urged them to act more quickly and decisively? For me, it also raises a more legalistic question: Why did the police officers, who are imbued by the American legal system with vast powers and equally vast protections, not rely upon those special societal privileges to do the right thing?

In virtually every other corner of American governance there is an implicit bargain to how things work. One might even call it a social contract: In exchange for their tax dollars, citizens get the services that come with a semi-modern state. Whether the American state in general is all that good at upholding its end of that bargain—and the bargain’s precise bounds—does not matter as much as its basic existence. We pay civil servants’ salaries, we buy them buildings and space shuttles and aircraft carriers and armaments galore, and we typically expect things from them in return.

Police departments are an awkward fit into this system, as I’ve noted before. In practical terms, under a web of statutes and court rulings, the cops have the power to do just about anything and the discretion to do almost nothing. By this, I don’t mean that cops don’t generally solve crimes or arrest suspects. But what I do mean is that when they don’t do those things—or when they do things they explicitly shouldn’t do—there are few to no ways to hold them accountable for it.

Perhaps the most illustrative example of the current legal landscape is Castle Rock v. Gonzales, a Supreme Court case from 2005. It also arose from an unspeakable tragedy. Jessica Gonzales, the lawsuit’s plaintiff, had begged the police department in Castle Rock, Colorado, in 1999 to enforce a restraining order against her ex-husband after he absconded with their three daughters. The officers made no efforts to locate or arrest him until her ex-husband showed up at the police station early the next morning and died in a shootout with the police. The officers then found the three girls’ bodies in the trunk of his car.

Gonzales sued the police department under Section 1983, the federal tort that allows people to sue state and local officials in federal court for violating their federal constitutional rights. She argued that the Colorado legislature had made enforcement of the restraining orders mandatory and that, as a result, the police had violated the Due Process Clause by not carrying it out. A federal district court judge ruled against her, as did a three-judge panel in the Tenth Circuit Court of Appeals. The Tenth Circuit then reinstated her lawsuit, after using a rare procedure to reconsider it with all judges taking part. The city then asked the Supreme Court to intervene.