the Tiananmen incident. Over a half million people left Hong Kong during the peak migration period from 1987 to 1996. Scepticism in the Chinese government's commitment to Hong Kong's future autonomy was further reflected by high demand for BDTC naturalisation. Even though BDTC status would expire after the handover in 1997 and carried no entitlement to UK right of abode, over 54,000 people applied for it on the final registration date in 1996 because the status qualified them to register as BN(O)s. Despite petitions from Governors David Wilson and Chris Patten asking for full citizenship to be conferred on the colony's residents, Parliament ultimately refused to grant all Hongkongers right of abode in the United Kingdom, citing difficulty in absorbing a large number of new citizens and that doing so would contradict the Joint Declaration. Instead, it offered citizenship to only 50,000 qualified residents and their dependents, through the British Nationality Selection Scheme. Because many departing residents were well-educated and held critical positions in medicine, finance, and engineering, the intention of the plan was to convince people within this professional core of Hong Kong's economy to remain in the territory after 1997. This limited grant of citizenship, along with the fact that the provision for nationality without UK right of abode was included in a memorandum of the Joint Declaration and not in the treaty text, has been used by proponents of conferring citizenship on BN(O)s to argue that granting it would not be a violation of that agreement. On the other hand, the Chinese government considers even these restricted grants to be a breach of the treaty and specifically disregards the British citizenship of those who obtained it under the BNSS. Legislative Councillors derided the Selection Scheme as a thinly veiled attempt by the British government to absorb only the wealthy and well-educated elite and accused the UK of abandoning the moral responsibility it had for subjects in the colony. Post-handover developments In the immediate years after the territory's handover, Chinese oversight of Hong Kong was considered relatively benign and hands-off. Because virtually all BN(O)s are also entitled to Hong Kong Special Administrative Region (HKSAR) passports, the UK-issued passports were redundant for international travel. Some residents sold these documents to people smugglers, who used them to assist illegal mainland Chinese migrants in passing through border control when they entered Western countries. BN(O) passports at the time lacked sufficient anti-forgery