It was probably the single most misleading poll published this year. On Nov. 2, Ann Selzer at the Des Moines Register published a poll which found Kamala Harris leading in Iowa by three points. This was considered huge news at the time both because Iowa was considered a safe bet for Trump and because Selzer was considered a very credible pollster. 

I chronicled some of the responses to the poll here. My favorite came from a column by Michelle Goldberg at the NY Times. Imagine this scene playing out in progressive homes across the country just prior to the election.

On Saturday evening I was watching a movie with my family when a text message made me gasp so hard that it scared them. “What happened?” my husband asked, worried. “Nothing bad,” I said, slightly overcome. “It’s just … Ann Selzer has Harris up three in Iowa!”...

So many of us were anxious to see how big Trump’s lead would be this time, and the fact that Selzer instead found him losing came as a shock.

But as we now know, Trump won Iowa by 13 points. It wasn't even close. Afterwards, Selzer published a self-serving column in the Register suggesting that maybe her poll had motivated Trump voters.

What a big miss for The Des Moines Register/Mediacom Iowa Poll. It followed an unprecedented worldwide fascination with an outlier poll showing Kamala Harris leading Donald Trump by 3 percentage points...

In response to a critique that I “manipulated” the data, or had been paid (by some anonymous source, presumably on the Democratic side), or that I was exercising psyops or some sort of voter suppression: I told more than one news outlet that the findings from this last poll could actually energize and activate Republican voters who thought they would likely coast to victory. Maybe that’s what happened.

If it did motivate a few Trump voters it didn't make a difference in the outcome and it doesn't explain how a renowned pollster was off by 16 points. A few days later, Selzer semi-retired, though she said it had been in the works for a year.

Last night, Trump sued Selzer and the Des Moines Register.

President-elect Donald Trump filed a lawsuit Monday night against the Des Moines Register newspaper and its highly respected former pollster, adding to his ongoing legal attacks against news media companies...

Trump’s attorneys filed the suit in Polk County, Iowa, where Des Moines is located, just days after ABC News settled a defamation lawsuit brought by Trump, agreeing to pay $15 million.

The ABC lawsuit was a defamation claim. The lawsuit against Selzer is different.

Unlike most of Mr. Trump’s other lawsuits against the media, which involve claims of defamation, this case alleged Ms. Selzer violated the Iowa Consumer Fraud Act, which prohibits deceptive practices that occur in sales or advertising.

“We believe this lawsuit is without merit,” said Lark-Marie Anton, a spokeswoman for The Des Moines Register. “We have acknowledged that the Selzer/Des Moines Register pre-election poll did not reflect the ultimate margin of President Trump’s Election Day victory in Iowa by releasing the poll’s full demographics, cross-tabs, weighted and unweighted data, as well as a technical explanation from pollster Ann Selzer.”

In other words, they are going to have to prove this was actual fraud by Selzer in which she intentionally misled the public.

Selzer would “have the public believe it was merely a coincidence that one of the worst polling misses of her career came just days before the most consequential election in memory,” the lawsuit claims. It later adds that the poll “was no ‘miss’ but rather an attempt to influence the outcome of the 2024 Presidential Election.”...

“President Trump, the Trump 2024 Campaign, and other Republicans were forced to divert enormous campaign and financial resources to Iowa” after the Selzer poll was released, the lawsuit claims. Federal campaign finance documents indicate that Trump’s campaign did pay about $254,000 to a Cedar Rapids, Iowa-based firm that does text message outreach on Nov. 4, the day before the election. That amount is equivalent to 22 cents of every $100 the campaign spent from Oct. 1 on...

“For too long,” the lawsuit argues, “left-wing pollsters have attempted to influence electoral outcomes through manipulated polls that have unacceptable error rates and are not grounded in widely accepted polling methodologies.”

I think it's fair to say that Selzer's explanations for the embarrassing failure have been self-serving and her inability to identify a reason for the error even after the fact seems odd. Still, it's a long way from that to proving fraud. I guess we'll see if discovery in this case turns up anything.