Politicians must be held accountable if their lies damage democracy, according to a former US federal prosecutor and FBI general counsel who was pursued by Donald Trump.

The US must be “as creative as possible” and introduce sweeping structural reforms if it escapes its current “mess”, said Andrew Weissmann, laying out a proposal for a legislative crackdown on election deceit.

“Lying can be held to account,” argued Weissmann, a senior figure in former FBI director Robert Mueller’s investigation of Russian interference in the 2016 presidential election, and Trump’s links to Moscow.

The former federal prosecutor remains a prominent voice against Trump and his assault on US institutions and justice, as a professor and analyst for liberal cable network MS Now.

Speaking from Paris, where he teaches for NYU, Weissmann said: “If we ever get out of this mess, what systemic reforms can we do? Because I think we tried going back to the old norms [under Joe Biden] and thinking that was going to be enough, and maybe it will be, but I just have been thinking a lot about, structurally, what we can do differently.

“I think the circumstances in the United States have made it imperative that we be as creative as possible.”

In a new book, Liar’s Kingdom: How to Stop Trump’s Deceit and Save America, Weissmann makes the case for major reform to hold political liars to account when their lies damage democracy itself, without falling afoul of free speech rights under the first amendment.

Weissmann proposes a Truth in Elections Act, built on existing law. The Stolen Valor Act of 2005, which criminalizes lying about military honors “with intent to obtain money, property, or other tangible benefit”, survived a US supreme court challenge.

Laying out his case for new legislation, Weissmann pointed to countries that protect elections from damaging lies. Examples include Brazil, where former president Jair Bolsonaro was jailed for election fraud lies that fueled a failed coup, and the UK, where, in 2010, Labour MP Phil Woolas lost his seat after falsely suggesting an opponent supported extremist violence.

“The principal argument against” strict policing of election lies is that it chills free speech, Weissmann said. “But I’m not very sympathetic to the idea that the solution to false speech is more free speech, for a variety of reasons. And if the issue is chilling some truthful speech, we have that problem now.

“Just to take MS Now as an example: we have a standards department … and you could view that as chilling speech, in the sense that they are going through pieces to see if everything is supported, does this pass a sufficient hurdle. We want to make sure we’re right, because lawyers are saying we don’t want to get sued.

“So defamation law definitely has some chilling effect, and I’m not sure anyone would say that’s a bad thing.”

Trump has been compared to famous figures in the world of organized crime, including John Gotti, “the Dapper Don”, who died in prison in 2002. Weissmann considers the strange case of Vincent “the Chin” Gigante, nicknamed the Oddfather, who avoided accountability by feigning mental illness, until federal prosecutors – led by Weissmann – proved competence, and secured conviction.

In such light, Weissmann places Trump’s public claims that the 2020 presidential election was stolen, setting the stage for the 6 January insurrection. It has been well-documented that Trump privately admitted Biden won.

In the second Trump administration, “the No 1 qualification we see in so many people who are nominated to incredibly important positions appears to be loyalty, rather than expertise,” said Weissmann. “I worked at the Department of Justice. I worked at the FBI. I don’t think anyone could say [current FBI director] Kash Patel was the very, very best person for the job of FBI director.”

Politicized prosecutions under Trump have included that of former FBI director James Comey. Last week, the DoJ announced a complaint against the DC Bar regarding disciplinary action against lawyers who backed Trump’s elections lie, with acting attorney general Todd Blanche calling the association “a blatantly partisan arm of leftist causes”.

Laughing, Weissmann said: “They said that also about the FBI. You know, I worked at the FBI. That was not my impression.”

But being on Trump’s enemies list is no laughing matter. Weissmann has twice been named in executive orders.

The first revoked security clearances for figures also including Biden, Hillary Clinton, Kamala Harris and Liz Cheney. Weissmann hadn’t held a security clearance since his time with Mueller. The second targeted law firm Jenner & Block for employing “the unethical Andrew Weissmann”.

Trump called Weissmann a “bad guy”, a remark that Weissmann writes in Liar’s Kingdom that “seemed like a mild upgrade from his speech at the Department of Justice weeks earlier in which he used the salacious but unedifying noun ‘scum’ to describe me”.

While a federal judge declared the order “null and void”, “the damage from this and other executive orders against law firms, academic institutions, and others is done”, Weissmann writes.

“Rather than find themselves on a governmental enemies list, they stay silent or complicit, as in the McCarthy era.

“They settle bogus lawsuits brought by Trump and his allies. They cede the defense of academic freedom to avoid losing critical scientific grants. They decline to bring good-faith litigation against administration policies so as not to become a target of illegal government retribution.

“I did not escape the effects of such submissiveness. In spite of Judge [John D] Bates’s ruling, law firms that were representing me quietly decided to withdraw. The publishing house that was first slated to release this book backed out within hours of Trump’s executive order about Jenner & Block – proof that fear works.”

Asked what it feels like to be singled out, Weissmann said: “You have to just get on with your life. But saying you get used to it, I don’t think that’s right. It’s not like it’s gone.”

In Paris, Weissmann’s walk to work takes in the Île de la Cité and the Île Saint-Louis, prompting him to compare the rebuilding of Notre Dame after the 2019 fire with work to come in the US after Trump.

“As somebody who grew up in the legal system, who’s an institutionalist, who sees the inside of courtrooms, when we’re looking at what parts of the government are still operating effectively, it’s the district courts,” he said. “That is a place where there’s due process, where facts matter, where there really is an ability to get at the truth. And you’re dealing with civilians: we have a jury system, and people do rise to the occasion and take it seriously.”

While Weissmann acknowledges that his proposal to test dangerous political lies in such courts has “flaws”, he said courts had “stayed with me as a place where you can still have due process, you can have a forum where truth matters”.

“When Trump or his acolytes challenged the election in 2020, that was in court, and he lost,” he said. “It’s different to just going to the public and saying whatever, regardless of whether it’s true or not.”

• Liar’s Kingdom: How to Stop Trump’s Deceit and Save America is out now