Localist Ventus Lau has won a legal challenge against a returning officer’s decision to bar him from standing in a Legco by-election last year, unseating the eventual winner, the Neo Democrats’ Gary Fan.

Returning officer Amy Chan rejected Lau’s bid to run in the New Territories East by-election on the grounds that he supported Hong Kong independence and would therefore fail to uphold the Basic Law.

The seat had been vacant due to the disqualification of independence advocate Sixtus Leung for failing to take his oath of office correctly.

In handing down his judgement on Friday, High Court judge Anderson Chow ruled that, similar to a legal challenge raised by Demosisto’s Agnes Chow over being barred in a Hong Kong Island by-election in 2018, the returning officer had failed to give Lau an opportunity to respond to the claims against him before making her decision.

The judge held that this failure amounted to a material irregularity in the by-election. As a result, he said, Fan had not been duly elected as a lawmaker.

But the judge noted that the returning officer did have the right to look beyond a declaration form Lau had signed stating he would uphold the Basic Law and pledge allegiance to the SAR, and the court ruling did not touch on whether the election official had come to the right conclusion.

A few months before his nomination for the by-election was rejected, Lau had publicly renounced the idea of independence for Hong Kong, saying he had changed his mind on this after realising that most people didn’t support the idea.

Speaking after the ruling, Fan said he respects the decision, but he’s disappointed that the court has affirmed that returning officers have the power to bar people from standing in elections based on their political stance.

Fan said he would meet his legal team before deciding whether to appeal against the ruling and it was too early to say whether he would stand in any future by-election for the seat.

Agnes Chow won her election petition early last week. Judge Anderson Chow nullified the result of the poll for the seat held by Demosisto’s Nathan Law before his disqualification, also over oath-taking.

Following that challenge, the judge ruled that the pro-democracy camp’s Au Nok-hin had not been duly elected.