[14] At the 2015 general election, Sobel stood in Leeds North West, coming second with 30.1% of the vote behind the incumbent Liberal Democrat MP Greg Mulholland.

[15][16] During the election, Sobel and the Leeds North West Labour Party were required to publish an apology leaflet and pay legal costs after falsely claiming that the incumbent Liberal Democrat MP Greg Mulholland voted for the Academies Act 2010.

[18] In October 2017, Sobel was elected as one of the officers of the All-Party Parliamentary Group on rare, genetic and undiagnosed conditions.

In October 2019 Sobel openly supported and spoke at an Extinction Rebellion occupation of Westminster, London despite warnings by the Met Police he could be arrested if he did so.

[22][23][24] In December 2019, he formed an All-Party Parliamentary Group aiming to reduce carbon emissions to net zero as early as possible.

In March 2021, Sobel wrote a letter to Robert Jenrick, the Secretary of State for Housing, Communities and Local Government, on behalf of Group for Action on Leeds Bradford Airport (GALBA).

[28]"I have requested that the split decision of the cross party plans panel to grant the new terminal and extend flight times at Leeds Bradford Airport be called in by the Government.

[29] In July 2023 the New Statesman named Sobel within a small list of Labour MPs who understand climate change.