His move in 2009 to the Clontarf local electoral area positioned Ó Ríordáin to run for election to Dáil Éireann in the Dublin North-Central constituency, which he did at the 2011 general election; he took the second seat on the fourth count with 10,192 votes. As a member of the Labour Party backbenches, he served as Vice-Chairperson of the Oireachtas Committee on Education and Social Protection and as a member of both the Finance, Public Expenditure & Reform Committee and the Good Friday Agreement Implementation Committee. He was reelected as a TD for the Dublin Bay North constituency in the 2020 General Election.
On 15 July 2014, Ó Ríordáin was appointed Minister of State with responsibility for New Communities, Culture and Equality at the Departments of Justice and Equality and Arts, Heritage and the Gaeltacht. As Minister of State he prioritised reforming the Direct Provision system, ending the legal entitlement of Church-controlled state-funded institutions to discriminate against LGBT people, and he played a key role in the Yes campaign in the 2015 Marriage Equality Referendum. On 28 April 2013, the Sunday Independent reported that Ó Ríordáin was secretly recorded by a pro-life activist as stating that the X-case legislation was only "the starting point", but that he would not state this publicly. As Minister of State for New Communities, Ó Ríordáin coordinated the Polska Éire 2015 festival, which was a week-long cultural and sporting festival in the run-up to the March 2015 Republic of Ireland v. Poland UEFA European Championship qualifier. In April 2015, Ó Ríordáin was appointed as Minister of State at the Department of Health, with responsibility for the National Drugs Strategy, in addition to his existing ministerial duties.
Ó Ríordáin's bid for re-election to the Dáil in Dublin North-Central at the 2016 general election was unsuccessful. However, he remained as a caretaker Minister of State for New Communities, Culture, Equality and Drug Strategy during the prolonged talks on government formation that followed, and was nominated by the Labour Party for election to Seanad Éireann. In April 2016, shortly before this period elapsed, he was elected to the 25th Seanad on the Industrial and Commercial Panel. Following his own success in gaining the Labour Party leadership, Brendan Howlin appointed Ó Ríordáin as Labour's Spokesperson on Environment and Sustainable Development, and Gaeltacht Affairs. On 10 November 2016, following the United States presidential election, Ó Ríordáin made a public statement in the Seanad that went viral on social media, in which he labelled President-elect Donald Trump as a "fascist" and a "monster", quoting Edmund Burke's attributed maxim that "the only way evil can prosper is for good men to do nothing". He condemned Trump's statements threatening to imprison his opponent, former Secretary of State Hillary Clinton, barring Muslims from entering the country, mass deportations, and his assertions that the media and the political system were rigged. Describing current events as an "ugly political crossroads", Ó Ríordáin declared that he was "embarrassed" and "frightened" by the reaction of TaoiseachEnda Kenny and the government, and sarcastically remarked that the government's reaction was to "ring up and ask them if it's okay to still bring the shamrock on St. Patrick's Day". He applauded SDLP leader Colum Eastwood's statement that his party would boycott the St. Patrick's Day ceremony at the White House during Trump's presidency. On 26 October 2017, speaking in the Seanad regarding a mortgage lending scandal, Ó Ríordáin referred to the bankers as a "shower of bastards" who are "getting away with murder, year in year out, in this democracy". He was admonished by CathaoirleachDenis O'Donovan for using unparliamentary language.
Return as TD and Labour Party leadership contest
Ó Ríordáin was elected for the Dublin Bay North constituency at the 2020 general election, getting 11.3% of the first preference vote. After Brendan Howlin's intention to stand down as party leader following the 2020 general election, Ó Ríordáin was nominated to contest the leadership election by Ged Nash and Ivana Bacik. Ó Ríordáin was also publicly supported by former Labour TD Liz McManus and former lord mayor of Dublin Andrew Montague. Launching his election bid, Ó Ríordáin said that Labour needed to rebuild its relationship with the public and had to get people to "trust us again". On 3 April 2020, it was announced that Ó Ríordáin had received 45% of the vote, with Alan Kelly the winner on 55%.
Other activities
On 28 March 2018, Paddy Jackson and his co-accused were found Not Guilty of rape and other charges. Following the verdict Ó Riordáin sent a tweet praising the complainant and questioning the jury's decision. In response Jackson's solicitors have announced that he intends to sue Ó Riordáin for defamation following a tweet Ó Riordáin made following Jackson's acquittal.
Personal life
He is married to Áine Kerr, Manager of News Partnerships at Facebook and former Managing Editor of Storyful.
