Something unusual happened over the past week that bears highlighting.

On Sunday, White House press secretary Sarah Sanders appeared on Fox News, where she argued for a wall on the border with Mexico by claiming that “nearly 4,000 known or suspected terrorists come into our country illegally” each year. This is not true; in fiscal year 2017, about 3,800 people on the terror watch list — a list criticized for its breadth — were either blocked at the border or before getting on a plane to the United States.

Kellyanne Conway, a senior adviser to President Trump, later acknowledged the mistake, calling it an “unfortunate misstatement” in an interview, again on Fox. Trump, in his speech to the country Tuesday night, didn’t mention terrorism at all — a bright spot of accuracy, however indirect, in a presentation otherwise littered with untrue, misleading or inflated claims.

That victory for truth, like all such victories, was short-lived.

On Wednesday evening, Trump retweeted several messages from Charlie Kirk, the enthusiastic head of a group focused on conservative millennials whose track record does not suggest a dogged adherence to accuracy. There was the time he claimed that a third of the murders in the United States were committed by undocumented immigrants, an obviously untrue claim. He’s repeatedly deleted tweets that included false information meant to boost support for the president.

And, most recently, he's had two of his tweets containing false or untrue information about immigration retweeted by the president.

The more recent tweet that Trump shared with his 57 million followers was this one.

The 17,000 criminals figure is accurate, according to Homeland Security, but there are three unmentioned asterisks: that the nature of the crimes committed by those individuals varies widely, that this is a tiny fraction of those who cross the border and that most of those criminals were stopped at existing border checkpoints, not trying to sneak illegally across the border.

The 1.7 million pounds of narcotics is also accurate, but requires a more urgent caveat: The vast majority of those drugs were similarly detected at border checkpoints. If you don’t believe us, believe the Drug Enforcement Administration or believe Trump’s former chief of staff John F. Kelly, both of whom made that point publicly.

That 6,000 gang members number is entirely incorrect. That figure is for both border stops and apprehensions by Immigration and Customs Enforcement officers anywhere in the country. A Homeland Security spokesman confirmed to The Washington Post that the actual number of gang members stopped at the border between border checkpoints — that is, attempting to enter the U.S. illegally — was about 800. That’s out of 397,000 such apprehensions in fiscal year 2018.

A bit before sharing that tweet, Trump had retweeted another tweet from Kirk.

This one, currently pinned at the top of Kirk's Twitter account, is worse.

Again, here’s what the DEA says about heroin crossing the border from Mexico: The bulk of heroin that enters the United States is smuggled in through checkpoints.

Excerpt from the 2018 National Drug Threat Assessment. (Drug Enforcement Administration) (Philip Bump/(Drug Enforcement Administration))

It’s not clear where the figure for the number of children being “sex trafficked” comes from. In the video accompanying the tweet, Kirk claims that “over 10,000 kids” cross the border as part of a trafficking effort every year, which would make up an unbelievable one-fifth of the total number of children apprehended crossing the border by themselves in fiscal year 2018.

The administration has tried to argue that the wall is necessary to prevent the trafficking of children, but the most recent data they produced identifies 170 people that came to the border in groups in the last six months of 2018 where the adults in the group weren’t related to the kids. That doesn’t mean the kids are being trafficked; they may have traveled to the border with family friends, for example.

Then there’s cost estimate, which, remarkably, is less than half the annual cost of illegal immigration most recently cited by Trump himself. Kirk’s more modest $135 billion apparently derives from a study from a group that seeks to curtail immigration and which employed a methodology deemed “fatally flawed” by the libertarian Cato Institute.

One flaw is that the report overestimates the number of immigrants in the country illegally. Over the past decade, the number of undocumented immigrants in the United States dropped by more than 1 million, according to Pew Research Center, lowering the cost estimates in that report. More problematically, the study also includes as costs government spending on the children of immigrants — many of whom are U.S. citizens — including things like education.

Revising the study's numbers to account for those and other factors, Cato pegs the annual cost at something more like $16 billion.

As we’ve said so many times before, Trump has access to much better information and data than what he can glean from skimming Twitter or watching Fox News. That he chooses to forgo that data in favor of amplifying people like Kirk is not new, but it does reinforce where Trump’s priorities lie.

He’d rather share misleading or false data that bolsters his argument than build an argument around data that comes from his own government. That his administration occasionally admits that it does so doesn’t do much to temper the problem.