While volunteering for the Mitt Romney 2008 presidential campaign, Nunberg met and was recruited by attorney Jay Sekulow to volunteer at the American Center for Law & Justice in an attempt to stop the construction of the Park51 mosque. While volunteering there he met political operativeRoger Stone, whom he has described as his mentor and "surrogate father". Nunberg began working for Trump, as a political and public affairs consultant, in 2011, after Trump decided not to run for president in 2012. Nunberg assisted in the writing of Trump's 2011 speech at the Conservative Political Action Conference. In February 2014 Nunberg was fired by Trump after he arranged a BuzzFeed interview that ended up being highly critical of Trump; the headline was "36 Hours on The Fake Campaign Trail with Donald Trump." Nunberg was rehired in April 2014 and was Trump's first full time hire for the Donald Trump for President 2016 Campaign; he was let go in December for undisclosed reasons. In February 2015 he was once again rehired by Trump, as a communications adviser for the Trump campaign, but was let go, shortly thereafter, by then-campaign manager Corey Lewandowski. Nunberg was rehired for a fourth time by the campaign in April 2015; between then and the beginning of July he was paid $85,139 by the campaign. Nunberg, along with Stone, helped prepare Trump for the first Republican debate, on August 6, 2015. Nunberg left the campaign in August, 2015 after continued tensions with Lewandowski. In March 2016 Nunberg endorsed Senator Ted Cruz for president, saying that Trump "does not have a coherent political ideology." In July 2016 Trump sued Nunberg for $10 million, accusing Nunberg of violating a confidentiality agreement by leaking information to the New York Post. In a legal response, Nunberg said that Trump might have illegally funneled corporate money into the campaign. Trump and Nunberg settled their legal dispute in August 2016.
March 2018 subpoena and media appearances
On March 5, 2018, Nunberg spoke to multiple cable news outlets and newspaper reporters without the knowledge of his attorney. He said he had been subpoened by a grand jury to testify and provide documents relating to Robert Mueller's Russia investigation, including all his email exchanges with Donald Trump, Roger Stone, and eight other people. He insisted he did not intend to comply with the subpoena, saying "Let him arrest me!" He also had in-person interviews with CNN'sJake Tapper and Erin Burnett and MSNBC'sKaty Tur and Ari Melber. He later backtracked, saying that he would cooperate fully with the subpoena, while expressing frustration at the large amount of documentation requested. On March 9, 2018 Nunberg testified before a federal grand jury for more than six hours, saying it was his, "duty as an American, whether I like it or not." Regarding the Mueller investigation, when asked whether he believed that the special counsel may have something on Trump, Nunberg responded, "I think they may." He added: "I think that he may have done something during the election. But I don't know that for sure." He also said "I have no knowledge or involvement in Russian collusion or any other inappropriate act" and that: "Donald Trump won this election on his own. He campaigned his ass off. And there is nobody who hates him more than me." Regarding Trump's former foreign-policy advisor Carter Page, Nunberg said that he believed that Page did collude with the Russians."