Libertarians, who believe in limited government and individual freedom, blame Trump, a Republican, for rushing through the creation of a Covid-19 vaccine when he was president and for not doing more to stop public health restrictions on the unvaccinated during the pandemic.
When Trump took to the stage in Washington, there were loud boos and jeers. A smaller section of the crowd, Trump supporters, cheered him.
Shortly before he appeared, one Libertarian Party member shouted: "Donald Trump should have taken a bullet!"
Trump's campaign did not immediately respond to a request for comment about the hostile reception.
Libertarians garnered only 1.2% of the national vote in 2020, or about 1.8 million votes, but November's election could be decided by just tens of thousands of votes in a handful of battleground states, so Trump is seeking to peel away some libertarian support.
Independent candidate Robert F. Kennedy Jr., who also spoke to the convention, was hoping to rally support.
Libertarian Party Chair Angela McArdle ruled on Sunday that Trump was not qualified to be the party's nominee for president, because he did not submit nominating papers.
"The reason I didn’t file paperwork for the Libertarian Nomination, which I would have absolutely gotten if I wanted it (as everyone could tell by the enthusiasm of the Crowd last night!), was the fact that, as the Republican Nominee, I am not allowed to have the Nomination of another Party," Trump said on Truth Social.
The party selected Chase Oliver, Georgia Senate election candidate in 2022, as the presidential candidate, it said on Sunday in a post on X.
TRUMP SAYS NOW A LIBERTARIAN
Trump, who was president between 2017 and 2021, immediately highlighted in his speech on Saturday (local time) his total 88 felony charges he faces in four federal and state prosecutions.
"If I wasn't a libertarian I am now," he said. He denounced the administration of President Joe Biden, his challenger in the November 5 election rematch, and Biden's fellow Democrats as being part of a "rise in left-wing fascism".
Trump was trying to appeal to libertarians, who have more in common with Republican policy positions than Democrats on issues including taxes and the size of government, in what is expected to be a closely fought election.
He added: "We should not be fighting each other." He asked libertarians to work with him to defeat Biden, an appeal which was greeted by many boos, although the vast majority in the crowd were fiercely opposed to Biden and his administration.
Trump's appearance at the libertarian gathering, unusual for a Republican White House candidate, also signaled how seriously he and his campaign take the threat of third-party candidate Kennedy, who has long opposed vaccines and mandates. Kennedy was quickly eliminated from the party's presidential nomination on Sunday.
Trump has been ramping up attacks on Kennedy, who is running as an independent, recently calling him a "fake" anti-vaccination proponent.
Kennedy addressed the party on social media on Sunday, writing "While we may not agree on every downstream issue, our core values of peace, free speech, and civil liberties make us natural allies."
Opinion polls suggest Kennedy will siphon votes away from both Trump and Biden, but it is not yet clear which of the major-party candidates will be hurt more by Kennedy's long-shot White House bid.
Libertarian Party organizers said Biden was also invited to speak to the convention but he declined to attend.
"The Libertarian Party can make a big difference. If we unite we will be unstoppable," Trump said to a mix of applause and jeers.
Trump said he was a "libertarian without even trying to be one," and that the Libertarian Party should endorse him, another line greeted by boos and jeers.
Undeterred, Trump poked fun at the crowd, saying if they did not back him, they would continue to garner just a tiny portion of voter support in national elections.
He pledged to put a libertarian in his cabinet if he wins the election, which was met by cries of "bullshit!"
Trump did get huge applause for one promise. A rallying cry for libertarians is the case of Ross Ulbricht, who is serving a life sentence for creating and operating the website Silk Road, which allowed users to secretly buy and sell drugs and other illegal products.
Libertarians believe Ulbricht's 2015 sentence represents government and judicial overreach. In front of a crowd holding "Free Ross" signs, Trump promised to commute Ulbricht's sentence if he wins back the White House.
