Claim: Gwen Stefani is the co-leader of No Doubt.
Evidence: She is the co-founder and lead vocalist of the band No Doubt that experienced major success after their breakthrough studio album Tragic Kingdom -LRB- 1995 -RRB- along with various successful singles , including `` Just a Girl '' , `` Do n't Speak '' , `` Hey Baby '' , and `` It 's My Life ''.