The sheriff is an outsized figure in the American imagination. He is Wyatt Earp, shooting it out with outlaws at the O.K. Corral. He is John Wayne, a lonely instrument of frontier justice. He is Rick Grimes, the resourceful survivor of a zombie apocalypse in “The Walking Dead.”

Now, along comes Scott Israel to remind us, despite the legend, how a sheriff can be a hack politician whose primary concern is protecting his own political reputation and little fief.

The Broward County sheriff, whose disgraceful performance in the Stoneman Douglas shooting has been a master class in evasion of responsibility, is the latest entry in why we don’t trust our public institutions.

It’s hard to imagine a more comprehensive and catastrophic failure from beginning to end than that of the sheriff’s office in the Parkland massacre. It ignored warnings that were specific and chilling about the shooter and at least one of its deputies waited outside the school while the shooting occurred. (And perhaps others did as well in the immediate aftermath.)

Sheriff Israel appropriately pronounced himself disgusted with the deputy, who has lost his job. But asked in an interview with CNN’s Jake Tapper on Sunday if he acknowledges that had his department acted differently the shooter might have been foiled, the sheriff responded with a flip rhyme, “ifs and buts were candy and nuts.”

It’s not as though the sheriff, mindful of the need to get a handle on his department’s handling of the case, has been quietly tending his own shop. At the CNN town hall last week, he turned in a crowd-pleasing performance. He opined about the new authorities that the police require and joined in lambasting NRA spokeswoman Dana Loesch to cheers from the audience.

He was emphatic about everything not touching on what officers under his authority did or didn’t do. When attention turned to that, he suddenly became mincingly precise and demanded to know more details about reported warning signs.

When Loesch cited media accounts of 39 calls to the police, Israel denounced the figure as categorically false. And the lawman was right — it was at least 18 calls.

What were these warnings? In 2016, a caller to the sheriff’s office said the perpetrator “planned to shoot up a school.” More recently, on Nov. 30, a caller told the sheriff’s office that the shooter was amassing weapons and “could be a school shooter in the making.”

The motto is that when we see something, we should say something. In the case of the Parkland shooter, people said something, over and over again, to little or no effect. The cliché after disasters is that no one “connected the dots.” In the case of the Parkland shooter, the dots were connected with bright lines.

Yet nothing happened, and the sheriff’s office had a large hand in that. Israel’s performance at the CNN town hall was even more shamefully dodgy when considering it’s likely that he already knew one of his deputies had done nothing to stop the shooter at the scene.

The sheriff’s theory of leadership apparently doesn’t extend down to the people working for him. “I gave him a gun,” he said of the deputy in another interview. “I gave him a badge. I gave him the training. If he didn’t have the heart to go in, that’s not my responsibility.”

The buck doesn’t stop with the sheriff, in other words; it stops with whomever he happens to give a badge and a gun.

Some supporters of gun control want to look away from the failures of law enforcement to keep the focus on the guns. But this is foolish for their own purposes — politically, there’s no chance of significant new laws if no one is held to account for glaring mistakes under the status quo.

If we take the imperative to do better seriously, Sheriff Israel and all his bureaucratic excuses should get the hell out of town.

Twitter: @RichLowry