A tape seized by the FBI that contains a secret recording by President Donald J. Trump’s longtime lawyer, Michael D. Cohen, of the two discussing payments to a former model just months before the 2016 election is “pretty clearly evidence” of federal campaign finance law violations, said Costas Panagopoulos, a political science professor at Northeastern with expertise in campaign finance.

The tape, seized by the FBI in a raid of Cohen’s office in April, was collected as part of a Justice Department investigation into Cohen’s involvement in paying off women in order to keep quiet embarrassing stories about Trump. News of the recording was first reported by The New York Times.

The scope of the investigation also includes whether Cohen paid adult film star Stephanie Clifford, whose stage name is Stormy Daniels, although the tape in question involves a separate person: Karen McDougal.

McDougal is a former Playboy model who spoke in March about a nearly yearlong affair she had with Trump.

When news of the tape broke on Friday, Trump’s personal lawyer, Rudolph Giuliani, confirmed to The Times that Trump had discussed payments to McDougal with Cohen on the tape. No such payment was ever made, however, Giuliani said.

Over the weekend, Trump took to Twitter to lash out at his longtime legal fixer.

“Inconceivable that the government would break into a lawyer’s office (early in the morning) – almost unheard of,” Trump tweeted. “Even more inconceivable that a lawyer would tape a client – totally unheard of & perhaps illegal. The good news is that your favorite President did nothing wrong!”

Complicating matters is a separate payment to McDougal. Prior to the election, the parent company of the National Enquirer, bought the exclusive rights to McDougal’s story, but never published anything—effectively silencing McDougal in the final months of Trump’s campaign. The chairman of that parent company is a personal friend of Trump’s.

We asked Panagopoulos about what all this means for Trump and for the midterm elections.

Based on what we know, and given your expertise in campaign finance, what do you make of the situation?

It seems pretty clear to me that there is enough evidence to support a claim that there was a violation of federal campaign finance laws in this election. It’s pretty clear to me that there were actions taken in order to silence someone from bringing up damaging information in a presidential election. It also seems pretty clear that there was a payment made, and that payment was not reported to the Federal Election Commission. This was an attempt to skirt federal campaign finance laws, and depending on how much investigators are willing to push this issue, this might be just the tip of the iceberg.

Do you think other information might turn up in the evidence seized from Cohen’s office?

This certainly causes people to wonder what else was taped. If Michael Cohen taped this one conversation, it seems likely he would’ve recorded others, as well.

The larger problem for this administration is that prosecutors and investigators are now in possession of a wealth of evidence, and Cohen himself seems to be on the brink of testifying. There’s potentially an endless amount of damaging information that could implicate the president on a wide range of issues.

These developments put the White House on the defensive during a week that was already very rough for them. The narrative keeps getting worse and worse for the White House, and that could quickly snowball out of control.

How might this affect voters in the midterm elections?

First, it’s important to recognize that Republicans are already facing an uphill battle in the midterms because the president’s party tends to lose seats in the midterm election cycle, as a general rule. So, they’re already up against that. It does help Republicans that there are signs the economy is doing well.

But these developments raise doubts about the president’s integrity and credibility, and raise the question of criminal wrongdoing. That will not help in 2018.

While investigators are still parsing through all the evidence they collected from Michael Cohen’s office, this tape just feeds into a larger narrative about the president misleading the American public, and possibly partaking in behaviors that are questionable at best and unethical or illegal at worst.

The more evidence for this outlook regarding the president, the harder it will be for Republicans to make a case to the voters.