Passage of the immigration bill has stoked fears that people could be barred from leaving Hong Kong if the immigration director so wishes.

The government says this is absolute nonsense and assured that the law - passed by a legislature devoid of opposition - will only apply to inbound flights when it is actually exercised.

People will still free to leave even if they go to the UK with BNO visas in large numbers.

The government undertaking to place the assurance in the form of subsidiary legislation is reassuring to some, though less so to others.

Strictly speaking, the promise of subsidiary legislation to confine the use of the extra power to incoming flights only represents a concession from the authority and may help to remove some of the local and international concerns.

The government might not have offered the concession had these concerns not been voiced.

For critics who are skeptical, the subsidiary legislation does not alter the fact that the director of immigration has had his power expanded by the law. The power to restrict exit is retained in the law books even though the use of it will be regulated.

As said, it marks a concession from the government. Hopefully, the subsidiary legislation will be ready before the principal legislation comes into effect in August when the number of Hongkongers emigrating to the UK is expected to reach a peak.

Nonetheless, there is a sense of deja vu.

Back in 2019 when the administration proposed the controversial extradition bill, it insisted that it was aimed at extraditing murder suspect Chan Tong-kai to Taiwan to face trial over the death of Hong Kong woman Poon Hiu-wing during a trip to the island.

But the broad scope of the bill, as the text was drafted, stoked immense fears in the public, leading to huge demonstrations and months of violent anti-government protests.

If the administration had acted similarly back then - as it is trying to address the fears this time to limit the damage before it is too late - the course of events that devastated Hong Kong over the past two years might have been different.

Has the government learnt from the past lesson? Let's hope so.

Throughout the latest controversy, the government insisted the newly passed law would help its battle against illegal immigrants and asylum claimants at source and would not affect people's constitutional rights of free movement.

It is apparent that this message failed to reach a large proportion of locals - especially among those with plans to leave Hong Kong this summer - as well as expatriates.

Either officers tasked with promoting the bill failed to explain it properly because they thought it was going before a legislature full of friends and no enemies - or the legislation was so badly worded that it could not be explained.

In either case, Secretary for Justice Teresa Cheng Yeuk-wah should be reprimanded for allowing her department to submit a half-baked bill that has to be immediately supplemented by a subsidiary legislation.

Deja vu on half-baked bill