In the early 1990s, due to the protracted lack of a permanent central authority, Somalia began to be characterized as a "failed state". Political scientist Ken Menkhaus argues that evidence suggested that the nation had already attained failed state status by the mid-1980s, while Robert I. Rotberg similarly posits that the state failure had preceded the ouster of the Barre administration. Hoehne (2009), Branwen (2009) and Verhoeven (2009) also used Somalia during this period as a case study to critique various aspects of the "state failure" discourse.