What Trump's conviction will and won't mean for the upcoming US elections

Now that the verdict has been reached and former President Donald Trump was found guilty on all counts, the question becomes: how will this impact public opinion and the election in November?

The short answer is that it will have only a small effect on public opinion, and by the time we get to November, it will be just another bullet point in Democrats' list of claims about why people should vote for Biden.

There is certainly going to be heavy coverage over the next couple of weeks, but voters' and the media's attention will soon turn to the next hot topic, such as speculation about the upcoming debate, Trump's other trials and who he'll choose for his running mate.

I make this claim because most of our political attitudes and behaviour are filtered through our partisanship. We can already predict how 80-85 percent of people are going to vote in November.

Thus, the verdict will have no effect on them. One might think that still leaves 15 percent or so of the electorate that could be swayed by the verdict. But what we know about most of these non-partisan individuals is that they also tend to be the least knowledgeable and interested in politics.

Thus, they are almost certainly not paying very close attention to what is happening right now. They won't start paying attention until September, at which point they will likely split about 60-40 one way or the other.

Authors Christopher Achen and Larry Bartels' 2016 book, Democracy for Realists, provides an outstanding summary of political science research that leads to these conclusions.

However, one doesn't need to read a book to understand this line of thought. The last two years of following Trump's legal trouble is a testament to how impenetrable partisanship is and how slowly political attitudes change, if at all.

Support staying strong

Not too long ago, we were all watching primetime congressional hearings on the investigation into what happened when the Capitol building was stormed by Trump supporters on January 6, 2021.

The speculation, at that time, was whether the US Attorney General, or any of the state attorneys general, would open an investigation into Trump and what the impact of those investigations would be on public opinion and the election.

We found out. The investigations started and nothing changed.

Then we speculated about what would happen if a former president was indicted for four different crimes. We found out that, in Trump's case, nothing would happen.

Trump was gaining popularity and putting a stranglehold on the Republican nomination, while being indicted.

Then we wondered if things would change when he was actually on trial and forced to sit in a courtroom rather than campaign. We all know the answer to that question. Nothing would change. Indeed, by the end of the trial, other Republican leaders were making trips to the courthouse to show support for their leader.

What's next

So here we are today. Speculation has run rampant about what the verdict will mean for the election. The trend line is clear. Public opinion might shift a small amount in the short run, but it won't have long-lasting effects. The changes that will occur are simply in the messaging of the campaigns.

Trump and Republicans have spent years inoculating their supporters from the effects of this and his other potential trials.

The guilty verdict now simply means that they'll have to push harder for a time to show that the case was a witch hunt. That it does not really matter and that others (such as President Joe Biden) must commit crimes as well - regardless of the voracity of the claim.

This is part of the reason partisanship has such a strong hold on us. Nothing happens in a vacuum. Our preferred party and candidates are always there to help guide our cognitive biases toward the answer we wanted in the first place: that our party is good and the other is bad.

On the other hand, Democrats will make this verdict one of the cornerstones of their non-issue oriented messaging. One can already picture the ads this fall featuring the "convicted" Trump.

The hope for Democrats is not that this will change people's minds and suddenly Biden will gain a bunch of new voters, but that it will affect the most important factor in determining who wins this November - that is, turnout.

Turnout is paramount

While there is a battle to gain an edge among non-partisan undecided voters, which could net a candidate 1-3 percentage points (nothing to scoff at in close elections like this one), the real battle is about getting your partisans to the polls.

Turnout will decide this election.

What we know about the effects of negative information about one's preferred candidate is that it doesn't, typically, lead one to vote for the other option.

It leads people to decide not to go vote at all. That's the big effect of negative stories. For example, the ongoing war in Gaza might hurt Biden in places like Dearborn, Michigan - not because residents are going to turn to Trump, but because they'll decide not to vote at all.

And in a battleground state like Michigan, that loss of voters could prove decisive.

Democrats are going to continuously remind people of this verdict in an attempt to reduce enthusiasm for Trump among his supporters and, therefore, decrease their likelihood of voting.

The 2020 presidential election saw the highest turnout in a century (about 66 percent of eligible voters), largely because people had such strong feelings about Trump. However, I expect that turnout will dip this year as it did in the 2022 midterm elections.

It remains to be seen how successful they will be at this. As we have seen over the last several years, nothing has motivated both Republicans and Democrats more at the ballot box than Donald Trump.