The Public Service Division said on 15 September that it is looking at the data and methodology of a working paper published this month by the National Bureau of Economic Research in the United States, The Straits Times reported. The PSD said it would refer the matter to the Corrupt Practices Investigation Bureau if there is a material basis to do so, and that it treats integrity concerns seriously.
What the paper claims
The paper, by economists Tomasz Piskorski of Columbia University, Amit Seru and Chun Zhao of Stanford University, and Jian Zhang of the University of Hong Kong, is titled "Do Social Norms Substitute for Enforcement? Evidence from Public Officials' Home Purchases in Singapore".
The authors linked records of home purchases to the Singapore Government Directory to identify buyers who were public servants. They then compared how often those buyers bought near MRT stations in the one to two years before the stations were announced, against buyers with similar profiles who were not in the public service.
They report that public servants bought near those future stations more often than the comparison group, that the effect was concentrated among mid-level officials and in agencies connected to rail planning, that a similar pattern appeared among relatives, and that the purchases produced meaningful gains.
What is not established
This is a working paper. NBER papers are circulated for comment before peer review, and this one has not been through it. The PSD's review is of the data and the method, and no one has been found to have done anything wrong. Whether any referral follows depends on what that review finds.
Why an announcement matters
The paper rests on something every property buyer already knows: a station changes the value of the homes around it, and the market starts to adjust from the moment the station is public. A buyer who knew before the announcement could buy ahead of that adjustment. That is the whole of the alleged advantage, and it is why the use of unannounced plans is treated as an integrity question rather than a lucky guess.
For everyone else, the lesson is about what you are paying for. Once a line or a station is announced, the seller knows about it too, and the asking price usually says so.
What to check when you buy near a new line
Judge what exists and what has been published. The URA Master Plan and the Land Transport Authority's announcements are public, and they are what every buyer and seller is working from. Roov's location tool shows the MRT stations within walking distance of any address today, the walk in minutes, and the bus that links you to the nearest station when the walk is long.
Price the wait as well as the station. A station due in several years is worth less to you today than one you can use now, and every year of waiting is a year of the commute you have. If a new line is part of why you are buying, check the purchase works without it: what you can borrow, the stamp duty, and what the home returns over your holding period. Our guide to how much you can borrow explains the limits.
In District 20, Thomson Reserve sits next to a station that is already open, Upper Thomson on the Thomson-East Coast Line, which is part of what a buyer there will be paying for. We looked at what that launch will have to compete with.