Drunken driving

I heard the news that alcohol have been detected from eight driver of bus of Hanshin Electric Railway Company by the test before work in this year. It is said that there was a driver who has commuted with the private car though they were under the influence of liquor.I felt strong resentment because I heard this news. The accident because of drunken driving happened frequently in the past and it became a problem so the regulation of drunken driving became severer.Why has this occurred yet? Especially, the driver of the bus is work to keep a lot of lives of the person. I think that they should have the sense of responsibility more. It is their mission to offer us safety and safety!