厚生労働省「労働時間等総合実態調査」に関する文献調査: 「前例」はいつ始まったのか

This paper reports the findings of a review of literature on a series of surveys on working hours in Japanese workplaces, conducted by the Ministry of Health, Labor and Welfare. The surveys have attracted public attention since Prime Minister Abe Shinzo deployed flawed data from the latest survey, conducted in 2013, to build up his argument for a labor reform bill in the Diet in January 2018. This scandal led to a partial retraction of the bill. An inspection team of the Ministry subsequently explored how and why flawed data were generated by the survey. However, the inspection team's report was inadequate: It only focused on how the 2013 survey carelessly replicated previous surveys. It left unresolved questions of how the past surveys were conducted, and how they affected labor policies. I reviewed primary and secondary literature on the series of surveys, which started from 1986 and deeply impacted the work of the deliberative council on labor policy, to uncover defects in the structuring of questionnaire s, sampling schemes, control of inspectors, statistical analysis, and result reporting. I observed symptoms of imprecise and incomprehensible explanations of various elements of the surveys by the Ministry in these 30 years, with no criticism leveled at the surveys before the scandal in the Diet in 2018.