Rowley was General Secretary of the Scottish Labour Party for one year; from May 1998 to May 1999. He was first elected to Fife Regional Council in 1990 when he was Chairman of Finance, and he later became the first leader of the new Fife Council, a position he returned to in 2012 until his election to the Scottish Parliament in 2014. Prior to his election as an MSP he was a Fife councillor and Labour Council Group Leader. He has three grown-up children, one of whom is Danielle Rowley; who was elected as MP for Midlothian at the 2017 snap election and also has a granddaughter. He worked as an education official with the TUC and worked for five years as an assistant, election agent and constituency manager to former Prime Minister Gordon Brown. He was considered Gordon Brown's right-hand man and protégé. He stood in the 2011 Scottish election as a Labour candidate for Dunfermline.
He declared his candidacy for the Scottish Labour Party's 2015 deputy leadership election, and was supported in his candidacy by trade unionsASLEF, CWU, NUM, Scottish Co-Operative Party, Socialist Health Association, TSSA, UCATT, and UNISON. He comfortably won the first round preferences of votes from the labour party membership and secured victory with over half the votes in the second round of voting. He was elected on 15 August 2015. Following Kezia Dugdale's resignation, he took over as acting leader of the Scottish Labour Party, until the new leader was elected. In September 2017, a leaked recording that was taken without permission and sold to the Scottish Sun newspaper of Alex Rowley at the Brighton Labour Party Conference led to accusations of a plot to oust Kezia Dugdale and replace her with Richard Leonard. Rowley said he backed Leonard to become leader to a member of the public, as well as party member, in a conversation that turned out to be a freelance journalist secretly recording the conversation undercover. Rowley had stated he would remain neutral, however was unaware of being recorded by what turned out to be a journalist trying to sell a story. Rowley apologised for the leaked recording, but strenuously denied being involved in or even aware of any plots within the labour party to remove Dugdale.
Shadow Cabinet
Rowley was Shadow Cabinet Secretary for Communities and Local Government from October 2018 until September 2019. During the 2019 Scottish budget process, Rowley was reprimanded by the Scottish Labour leader due to Rowley's personal discussions with the SNP Finance Secretary about supporting the budget in exchange for cuts to local government being substituted for Higher Education cuts in breach of Scottish Labour Party policy and undermining the budget spokesperson James Kelly. Rowley became Shadow Cabinet Secretary for Brexit and Constitutional Relations in September 2019.
Personal life
On 15 November 2017 Alex Rowley resigned as deputy leader after his former partner took to a newspaper, again The Scottish Sun, to accuse him of sending her disrespectful text messages. The woman refused to reveal her identity, and the alleged incident had happened almost four years previously, before being sold to The Scottish Sun newspaper. Rowley denied the allegations, referred himself for investigation and said he would clear his name. The Scottish Labour Party issued a statement saying: "Alex Rowley has stood aside as Interim and Deputy Leader of Scottish Labour and referred himself to the Party's internal complaints procedure regarding allegations made against him." A Scottish Labour spokesperson also said: "At no point did the Labour party receive a formal complaint regarding Alex Rowley. The party was approached by newspapers with unsubstantiated claims, with no evidence shared with the Labour party prior to publication in the Sun newspaper." The former Scottish Labour leader Kezia Dugdale issued a statement calling for Rowley to be immediately suspended from the party while the investigation was ongoing. Leadership candidate Anas Sarwar also joined calls for Rowley to be suspended while the investigation was carried out. Rowley claimed there was a determined attempt to use the media to damage him and his family for political purposes. The investigation concluded that there was no case to answer.