Charging market rent to public housing tenants whose income and assets both exceed prescribed limits, a policy set to be endorsed by the Housing Authority later this month, will probably succeed in encouraging many rich tenants to vacate their flats. But it is almost certain some of these tenants, for various social and personal reasons, will be happy to pay market rent to maintain their right to live in their existing flats. Should the Housing Authority (HA) then consider using the ultimate weapon of eviction so that the units they occupy can be allocated to the really needy? In announcing the market rent measure, the Housing Authority committee which drew up the policy, said it had not ruled out eviction. It said eviction was justifiable, but was not pursued because it did not want to create anxieties in the politically-sensitive transition period approaching the handover in 1997. But it is difficult to see how the HA can carry out evictions. Tenants who pay market rent can argue they should be allowed to maintain their tenancy because they will no longer be receiving rental subsidies. After all, in the private sector the Landlord and Tenant (Consolidation) Ordinance provides that the landlord cannot evict a tenant unless he wants to occupy the flat himself. The HA can counter that public housing units are built for the needy and cannot be equated with flats in the open market. Under the Housing Ordinance, the Housing Authority can determine which categories of people can live in public housing estates. Be that as it may, eviction may still be difficult unless the HA rejects the market rent policy, which may be hard to undo once it is introduced. One argument against eviction is that the incomes of today's rich households may fall in time as grown-up children move out to set up their own families. The market rent policy gives the remaining elder members of the households the flexibility of paying subsidised rents when their incomes fall. If we accept the income of a household can fluctuate, then it is debatable whether we should evict a household when it is rich, knowing that its wealth may decline in the future. Theoretically, a rich household which has been evicted can re-apply for public housing when it becomes less well-off. But this will cause hardship in practice because the waiting list for public housing is very long. A likely outcome of the market rent policy is that households which have fears of a fall in income in the future will be willing to pay market rent for their flats. Others may also be happy to pay higher rents so that they can keep their flats for elder members of the households who may not want to live with their children or vice-versa. There are also those who want to continue to live in the same addresses because they are close to work and their relatives. Indeed, while eviction is the most logical way of maintaining the integrity of the public housing programme as a form of welfare, there are strong social and personal considerations against it. So far, the HA's policy has been to encourage the more well-off tenants to buy Home Ownership Scheme (HOS) flats so that their vacated units could be taken up by the needy. While the direction is right, the HA must also accept the fact it is virtually impossible to keep all public housing tenants poor forever. A sense of belonging is often associated with home ownership. But why should a public housing tenant be forced to move out of an estate which he has grown to love? Let him pay market rent so that he can continue to mix with his old kai fongs and patronise his most favourite restaurant. There is nothing wrong with the rich living alongside the poor. In fact, this is a desirable social mix which should be encouraged. It is argued if rich tenants do not move out, then the size of the public rental housing programme can never be trimmed and its waiting list can never be shortened because the population is growing. This is a valid consideration. But a far more effective solution is to give those on the waiting list an extra option of buying flats at affordable prices so that they would not become public housing tenants in the first place. In the light of the Legislative Council's passage of a motion in February calling on the HA to sell public rental flats to sitting tenants, the HA is understood to be exploring several ways of meeting the demand. One option is said to be selling new rental flats at a price lower than that of HOS flats to public rental housing applicants and sitting tenants. This sounds desirable because one complaint about the HOS is that the flats, though priced at a discount to the market price of similar private flats, are still too expensive for poor households. The allocation of public housing resources must be rational. While eviction is a very rational policy, it is not necessarily reasonable or socially desirable.