Experimenting widely within alt rock since their conception in 1999, the band's lineup often changed around lead singer and guitarist Ted Leo, whose humanist songwriting is reminiscent of Joe Strummer and Billy Bragg. Leo's solid intellectual punk sound is evident throughout, with 2001's The Tyranny of Distance nodding towards Celtic and folk rock. Shake the Sheets in 2004 is particularly strong on social commentary, and thanks to regular tours, the band are recognized as one of the most prolific and vital on the indie scene.