Nguyen was appointed to the Garden Grove Unified School District Board of Education in 2011,[5] after a close race in 2010. He was elected as a trustee in 2012, and served a term as vice president. As a board member, he fought against the exclusion of LGBT Vietnamese from the annual Little SaigonTết Parade.[6][7] He resigned from the board of trustees in 2014 due to becoming mayor.[8][9]
Nguyen defeated incumbent Bruce Broadwater by 15 votes in the 2014 election to become mayor of Garden Grove. He also became the first Vietnamese-American mayor of the city.[10] As mayor, he sought to improve government transparency and accountability, and to engage voters by making city finance records available online.[11][12][13] Nguyen was appointed by the state governor to the Orange County Fair and Event Center Board of Directors.[1][14] He resigned the position in 2015.[14]
The president of the Garden Grove Police Association, a political opponent of Nguyen, "surreptitiously recorded a conversation" in June 2015 with Nguyen, then newly elected mayor.[15] According to the OC Weekly, "during the discussion, Nguyen called [Garden Grove] City Councilman Phat Bui 'a fucking dick,' a reference to efforts by Bui's supporters to label Nguyen a communist sympathizer for not vehemently protesting Riverside's sister-city relationship with Can Tho, Vietnam". Nguyen stated the insinuation was inaccurate and that he simply "didn't think one city council should tell another what to do".[15]
In the 2016 elections Nguyen ran for congress in California's 46th district, long held by Loretta Sanchez, with former California State Senate member Lou Correa as his opponent.[16][17] In the June primary Nguyen came in second with 14.6% of the vote after Correa received 43.7%.[18][19] In the November Nguyen lost to Correa after receiving just under 30% of the vote in the general election.[20]
Nguyen's term as Garden Grove mayor ended in December 2016, and he was succeeded by council member/Mayor Pro Tem, Steve Jones.[21][22]
