From 2007 to 2014, again in 2021 and since 2024, he played with Morrissey and appears on his albums Years of Refusal and World Peace Is None of Your Business.
He began playing electric and upright bass at age 12.
[3] Early in his career, Walker was a member of the groups Year of the Rabbit, The Joy Circuit, and Cupcakes (1996-2000).
[6] On November 6, 2014, Morrisey announced that Walker was granted a leave of absence from the band, for "compassionate reasons".
[9] In 2022, he appeared in the music video for the song "Kick Ass".