There is more to an accident inquiry than just apportioning blame. Concluding a three-month investigation into a train crash during an overnight test of a new signalling system in March, the MTR Corporation laid the blame squarely on a contractor for the errors made in a software upgrade in 2017. A government probe into the incident in turn criticised the train operator for being overreliant on the contractor. The findings came as no surprise amid a series of woes for the city’s rail operator in recent years. But whether they can address the inadequacies along the chain of supervision is another matter. It was sheer luck that only one driver sustained minor injuries when two empty trains collided at the crossover junction near Central station during the drill. But the severity of the incident was reflected in the subsequent disruption of services caused by the derailment and the indefinite suspension of the signalling tests. Most MTR workers set to get pay rise of at least 4.2 per cent According to the MTR Corp, contractor Alstom-Thales DUAT Joint Venture made three implementation errors when performing a software change, which it said had reflected the contractor’s inadequacies in upholding quality assurance, risk assessment and simulation. Experts in the parallel investigation by the government raised further questions, saying the MTR Corp ought to have been aware that the software did not fully comply with international standards and contained “latent anomalies that might result in an unacceptably high risk of an unsafe incident”. The MTR Corp is the first in the world to install a second backup signalling system aimed at boosting service reliability to 100 per cent. While the commitment for better services is to be commended, there is no room for error with a system used by millions of people each day. The problems identified sit oddly with the MTR Corp’s reputation as a world-class rail operator. The collision came after an array of works irregularities had come to light. The rail giant must keep a close watch on its projects and be held responsible for any faults with its works and services. But the buck does not just stop here. The government, being the supervisor and key shareholder of the MTR Corp, is ultimately accountable, too.