【明報專訊】THE RECENT STRIKE staged by the subcontracted cleaners of Hoi Lai Estate in Cheung Sha Wan has brought up a string of questions. The complex relationship between the incoming and outgoing service contractors has aroused concerns about collusion in labour exploitation or bid-rigging. The incident has necessitated a review into whether the Housing Department has fulfilled its supervisory responsibilities in monitoring the process and whether there are loopholes in the tendering system. The Housing Department is responsible for closely monitoring tenders submitted by contractors. Any failure to spot suspicious bidding is negligence of duty. The authorities should never tolerate the exploitation of grass-roots workers. The Housing Department must do justice to the cleansing workers and give the public a clear account of the case.