SMRT revealed its staff may have doctored maintenance records – a likely cause of the unprecedented flooding in an MRT tunnel. Insight delves into the questions thrown up by the episode.

There's a need to address questions like what prompted the staff to do what they purportedly did, and how they managed to go unchecked for so long.

Staff from at least one department in SMRT have admitted to lapses in response to a company call to own up – without penalty – before a wide-scale audit is launched.