Under opposition leaders Bill Shorten and Anthony Albanese, she held the portfolios of preventing family violence (2016–2018); employment services, workforce participation and future of work (2018–2019); young Australians and youth affairs (2018–2019); and the environment and water (2019–2022).

[1] In July 2015, Butler along with Labor colleague Laurie Ferguson, Liberal MPs Warren Entsch and Teresa Gambaro, independents Andrew Wilkie and Cathy McGowan and Greens MP Adam Bandt, co-sponsored a bill to introduce same-sex marriage in Australia.

[15] In 2016, Butler was sued for defamation after an appearance on Q&A in which she implied Calum Thwaites, a Queensland University of Technology (QUT) student, had used a racial slur in a Facebook post.

[16] Butler and Thwaites settled out of court, as a result of which she offered "my unreserved apology for enabling those meanings about you to be conveyed, and for the distress and damage to your reputation caused as a consequence".

[17] At the 2022 federal election, Butler lost her seat of Griffith to Max Chandler-Mather of the Australian Greens, despite the ALP receiving a nationwide positive swing and forming a majority government.

Unusually, despite being an incumbent, she was not one of the final two candidates in the two-candidate-preferred count for the seat; her preferences helped the Greens beat Olivia Roberts of the Liberal National Party.