As the Taxgate commission begins its work tomorrow, many political analysts are speculating that the investigation into a 2011 Tax Ministry leak of PM Helle Thorning-Schmidt's audit will seriously and permanently change the face of Danish politics.

The decision by Thorning-Schmidt (Socialdemokraterne) to go on the offensive and pre-emptively strike down a comment in the audit that insinuates her husband Stephen Kinnock is gay has been viewed as both a wise strategic move and a definitive sign that the era in which a politician’s personal life was off limits is now over.

“I cannot cite a precedent in which a politician has gone out and commented on such private details in the press,” Mark Blach-Ørsten, a professor at Roskilde University who studies political scandals, told Politiken newspaper. “There have been previous rumours about various politicians, but none of them up until now has chosen to go public and comment on them.”

Blach-Ørsten said that Thorning-Schmidt’s decision could set the tone for an irreversible decline.

“Sex is the last bastion in a politician’s private life that is now set to fall,” he said. “One fears that we are approaching the types of dirty tricks that we know from American politics and Danish television shows.”

Anders Esmark, a political science professor at the University of Copenhagen, agreed.

“That the country’s prime minister could accept the logic that it is relevant for her to comment on the rumours is an acknowledgment that the focus of Danish politics has shifted to the invidual,” Esmark told Politiken.

Rasmus Jønsen, a professor of political communication at Roskilde University, said that voters share some of the blame for this development.

“The mindset in Christiansborg has largely become that you need to use negative campaigns and go after the person instead of the politics precisely because individual personalities have become so important in how the public votes,” Jønsen told Politiken.

But while many bemoan this new trend, Thorning-Schmidt has been praised for getting out ahead of what could have been a more damaging story, both by addressing the gay rumours and by choosing to publicly release all nine pages of the original investigation into Kinnock’s tax obligations.

“By going to Politiken themselves and refuting the rumours, the prime minister and her husband decided the time and place and also, to a large degree, the way in which the rumours came out,” Christine Cordsen, the political editor for Jyllands-Posten newspaper, wrote. “Helle Thorning-Schmidt has now done what she can to ensure that the interest first and foremost is in [opposition party] Venstre’s potential misuse of power when the commission’s hearings get underway.”

In that regard, there are some signs that Thorning-Schmidt’s tactic may work. The commission’s investigation is expected to see journalists, political spindoctors and top politicians take the witness stand, including the former prime minister, Lars Løkke Rasmussen (Venstre), and the former tax minister, Troels Lund Poulsen (Venstre).

“On a scale of 1-10, it could end up just being a 2-3. But it could also end as a 10,” Roger Buch, a political science professor at the Danish School of Media and Journalism, told BT tabloid. “Ultimately, it could cost Troels Lund Poulsen and Lars Løkke Rasmussen their careers and change the political landscape if it turns out that they were involved in, or were aware of, a leak or an attempt to affect [tax authority] Skat’s outcome.”

Speaking to Jyllands-Posten, Buch predicted that the leaks in the case will be revealed to be much larger than previously believed.

At the heart of Taxgate is a 2010 audit of the finances of then-opposition leader Thorning-Schmidt and Kinnock, who at the time worked and lived part-time in Switzerland. Kinnock did not pay taxes in Denmark, and the investigation ultimately declared that he did not owe Danish taxes. The confidential audit was leaked to BT prior to last year's general election. Peter Arnfeldt, Poulsen’s spin doctor, was reported to the police for the leak and Poulsen was forced to take a leave of absence from parliament. Rasmussen’s top aide also admitted to being involved in meetings about the audit.

But the commission’s investigation seems likely to turn up even more potential leaks.

“The case has the potential to open up as an administrative and political scandal, and at the heart is the question of how confidential information on the couple’s tax situation could have made its way out of Skat’s walls,” Berlingske newspaper’s political commentator, Thomas Larsen, wrote. “It won’t be pretty.”