Washington DC - A Democratic Senator is calling for a criminal investigation into Health and Human Services Secretary Robert F. Kennedy Jr. over alleged lies he told Congress.

In a report published Thursday, The Guardian detailed how newly obtained documents undermine testimony Kennedy gave during his Senate confirmation hearings last year, where he claimed a 2019 trip to Samoa had "nothing to do with vaccines."

In reaction, Senator Ron Wyden of Oregon told the outlet he would be pressing his Republican colleagues, who currently maintain the majority, to issue a criminal referral of Kennedy to the Department of Justice for a criminal investigation.

"RFK's platform is built on lies and grifts that leave a trail of dead children in their wake," Wyden said. "There are consequences for lying to Congress."

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Kennedy – a longtime anti-vaccine advocate – took the trip to Samoa when the island was dealing with a measles outbreak. Though he has repeatedly insisted the visit was not related to vaccines, documents and letters contradict his claims.

Months after his visit, the outbreak worsened, sickening thousands and killing 83 people, many of whom were children.

He has since faced heavy criticism for stoking anti-vaccine sentiments in the region, which some believe led to the deaths.

Alongside Wydon's call, the government watchdog group American Oversight sent a letter to the DOJ that same day urging the department to investigate whether the secretary broke the law with his lies.

For a criminal investigation to be launched, it would have to be executed by the DOJ, which seems highly unlikely while Donald Trump is president and Republicans control both the House and Senate.

But Wydon argues that if his party manages to take back control in the upcoming November midterms, then the tables could turn.

"When Democrats retake the majority in the Senate, RFK will be at the top of the list of Trump officials the finance committee will hold accountable for endangering American families," Wyden said.