The Epstein files have shaken Norway’s faith in democracy, the head of the Norwegian parliament’s oversight committee has said, as a sprawling investigation into the connections between its foreign office and the late sex offender gets under way.

An independent commission to look into information brought to light by the Jeffrey Epstein documents released by the US Department of Justice was launched on Wednesday after the Norwegian parliament voted unanimously last month for it to be set up.

The commission has been instructed to go back more than 30 years, to include the lead-up to the 1993-95 Oslo accords, examining relationships between Epstein and his network and current or former Norwegian politicians and civil servants. The commission will look at whether these relationships had any “consequences for Norwegian interests and security”.

It is also mandated to look at Norwegian campaigning for leadership positions in international organisations and the allocation of development aid and other public funding to them.

The release of the Epstein files in January sent shockwaves through Norway after several figures across the foreign office and royal family were named in them.

Per-Willy Amundsen, the chair of the standing committee on scrutiny and constitutional affairs in parliament, which appointed the independent investigation into the Epstein files, said Norwegians typically saw themselves as “an open and democratic and well- functioning society without corruption”. But the Epstein files had damaged trust in politicians in the eyes of most people, he added.

“So in a sense it has struck us very hard. And therefore we are completely dependent on having to try to build that trust again,” he said. “And therefore it is very important to have a completely independent commission that gets very free hands, protection by law, to find the facts and present them to the Storting [parliament].”

Several police investigations are already under way, and the commission will pass on any relevant information they discover to the police.

Amundsen, who is a member of the far-right Progress party (Fremskrittspartiet), said: “It is very central people in the Norwegian political establishment [who are named in the Epstein files] and we have to find out how deep this runs. And also find all the facts so that people can rebuild their trust in Norwegian institutions.”

There are fears the Epstein files could have an impact on Norway’s international reputation as a peace broker and advocate of peace.

“This is very much something that should worry, and worries many, in Norway,” said Amundsen. “We have had this reputation internationally and this is a case that may change that view of Norway. But also, therefore, it is very important to find the facts and pursue the truth, to get that trust in the people, but also in foreign relations.”

The commission will not, however, be looking into crown princess Mette-Marit’s involvement with Epstein, which the constitution stipulates is not a matter for parliament. But, Amundsen said, their findings may well have political ramifications, particularly for the ruling Labour party.

“They have been the party that has been most in government since the last world war, they have a broad network of people in diplomacy and have been ruling the ministry of foreign affairs for very many years,” he added.

Speaking last month, the Labour prime minister, Jonas Gahr Støre, said the Epstein files had clearly shown “it is possible to buy and abuse influence if you are rich enough”.

Støre said that connections between Norwegians in “trusted and central positions” had been “proven” in the Epstein files, adding: “Reasonable questions have been raised about whether the links are in violation of the law and many aspects of society’s ethical regulations.

“It is crucial that these circumstances and the questions they raise are clarified, and that the facts are brought to the table.”