Is the exposure of an incessant stream of politicians who have not paid their pension premiums the result of a crusade to regain public trust in the pension system, a hysterical witch hunt or merely a political power struggle ahead of a key election?

Experts and political insiders say that all three theories have played a role in the ongoing scandal.

Veteran lawmaker Ichiro Ozawa was the latest domino to fall, stating Monday that he would not accept the presidency of the Democratic Party of Japan in light of his failure to join the pension system from April 1980 to March 1986.