In handing down sentences for subversion to 45 opposition figures on Tuesday, the High Court named four of them as "principal offenders", with former legal academic Benny Tai deemed as the initiator of an unofficial legislative primary election in 2020 aimed at overthrowing the government.

Tai received the heaviest jail term of 10 years among all defendants.

The three presiding national security judges – Andrew Chan, Alex Lee and Johnny Chan – considered a starting point of 15 years behind bars for Tai, and reduced that by one-third after he pleaded guilty to conspiracy to commit subversion.

“​​In short, [Tai] was not only the initiator of the scheme, but also an organiser of the primary election… He was the mastermind behind, hence could well be placed in the ‘[principal] offender’ category,” the judges wrote.

“[Tai] might not be the one standing in the primary election or the actual Legco election, he however provided the necessary platform for those who intended to exercise the vetoing power under the scheme.”

Three others – former lawmaker Au Nok-hin and former district councillors Andrew Chiu and Ben Chung – were also named “principal offenders”.

They had pleaded guilty and become prosecution witnesses in the trial.

The trio received jail sentences of six years and one month to seven years each.

With starting points of 12 to 15 years in jail, the judges said the three had their sentences reduced for assisting the prosecution in the trial, as well as other mitigation factors.

The court heard that the conspiracy in this case was aimed at undermining or overthrowing the political system and structure of the Hong Kong SAR.