Police move people on as they gathered in the Causeway Bay district of Hong Kong on June 4, 2021, after police closed the venue where Hong Kong people traditionally gather annually to mourn the victims of China's Tiananmen Square crackdown in 1989 which the authorities have banned citing the coronavirus pandemic and vowed to stamp out any protests on the anniversary.

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Hong Kong CNN  — 

The fates of many of Hong Kong’s leading pro-democracy figures are at stake in two ongoing trials that spotlight the impact of the Beijing-imposed national security law on the once outspoken city.

On Monday, hearings began in the closely watched trial of media mogul Jimmy Lai, a major figure in Hong Kong’s press landscape who has been accused of “colluding with foreign forces.”

And last month, lawyers made closing remarks in a separate national security case against dozens of activists and politicians known as the “Hong Kong 47.” The defendants, including former student activist Joshua Wong, were arrested en masse nearly three years ago for holding an unofficial primary election to decide who should contest city lawmaker elections.

The twin trials are among the highest profile to date under the sweeping national security law imposed by Beijing in 2020 in the wake of massive and at times violent pro-democracy protests in 2019.

Authorities in Beijing and Hong Kong say the law “restored stability” and closed loopholes that allowed interference of “foreign forces.” They’ve denied the law has suppressed freedoms.

But rights organizations, media groups, and critics say it has transformed the legal landscape and slashed basic civil and political rights in Hong Kong – a city once known for its robust culture of protest and free press and lauded for its international standard legal system.

What the courts decide in both trials will send a strong signal of how political acts — which many argue were in line with the normal functioning of the city’s vibrant civil society — are now treated.

The trials, whose verdicts are expected next year, also come as Hong Kong plans to expand the number of national security crimes with new legislation. Officials say a new law will plug “gaps” in Beijing’s rules, but critics fear it could further degrade freedoms – and international confidence – in the city.

Here’s what you need to know: 

Who’s on trial and what are the charges?

Lai, 76, was among the first people to be arrested under the national security law after it came into effect on June 30, 2020. He is now on trial for three counts of colluding with foreign forces under the national security law and a separate charge under the city’s colonial-era sedition act. Lai has pleaded not guilty to all charges.

The founder of the pro-democracy, anti-Beijing newspaper Apple Daily had already been jailed for roughly three years and handed other sentences in relation to the protests and business operations at the paper’s premises.

Lai had long been an outspoken critic of China’s ruling Communist Party – a view reflected in the pages of his now-defunct newspaper. During the 2019 protests, he traveled to the United States to meet with politicians to discuss the political situation in Hong Kong – a move seen by Beijing as colluding with foreign forces to undermine China’s security.

The so-called Hong Kong 47 includes seasoned politicians, elected lawmakers and young protest leaders, as well as academics, unionists, journalists and medical workers. They hail from multiple generations and a wide political spectrum - from moderate pro-democracy figures to those who advocate for Hong Kong’s self-determination.

Among some of the more well-known figures are Joshua Wong, 27, who gained international fame as the teenage face of Hong Kong’s years of student-led democracy protests; Benny Tai, 59, a legal scholar and co-founder of the 2014 Occupy Central movement; and Claudia Mo, 66, a former journalist-turned-legislator.

They were charged with “conspiracy to commit subversion” after holding the unofficial primary election in 2020 less than two weeks after security law came into effect. Its goal was to decide who should contest city lawmaker elections and give pro-democracy politicians the best chance of gaining a majority in the legislature. Hundreds of thousands of people cast votes.

Those on trial say that plan was simply part of the pluralistic, oppositional politics that has long been permitted in Hong Kong. Prosecutors argue it amounted to a “massive and well-organized scheme to subvert the Hong Kong government.”

In national security trials, the maximum sentence is life in prison.

TOPSHOT - Police lead Hong kong pro-democracy media mogul Jimmy Lai (C), 72, away from his home after he was arrested under the new national security law in Hong kong on August 10, 2020. - Hong Kong pro-democracy media mogul Jimmy Lai was arrested under a new national security law on August 10 and police raided his newspaper offices in a deepening crackdown on dissent in the restless Chinese city. (Photo by VERNON YUEN / AFP) (Photo by VERNON YUEN/AFP via Getty Images)

How are national security trials different from other proceedings?

The national security law, drafted and approved in Beijing for Hong Kong, criminalizes acts of secession, subversion, terrorism, and collusion with foreign forces.

It also allows for departures from common law in terms of how cases are tried.

So far, no national security cases in the city have been heard by a jury. They’ve instead been presided over by a bench of three high court judges selected by the city’s Beijing-appointed Chief Executive. The judges come from the existing ranks of the city’s judiciary and are chosen based on their “judicial and professional qualities,” the government has said.

According to official figures provided to CNN on Tuesday, 172 people have been charged under the national security law as of this week. Of the more than 100 completed trials there is a 100% conviction rate, according to data collected by Georgetown University’s Center for Asian Law research fellow, Eric Yan-ho Lai.

The law provides an option for cases to be transferred to mainland China for trial under extreme circumstances – a provision that has yet to be used.

It also places a higher threshold for bail. In the trial of the 47, 32 defendants were denied bail and have been in detention since 2021 – a highly unusual practice for non-murder cases. Two more had bail revoked for breaching conditions.

In another departure, Hong Kong courts must get the approval of the city’s leader before allowing a foreign lawyer without local qualifications to represent defendants in national security cases.

Lai, who is a British citizen, has been blocked from being represented by a British lawyer, a decision undergoing a separate legal challenge that has repeatedly delayed this trial’s start date.

The government in recent months has also issued bounties for overseas-based and self-exiled activists, including some foreign nationals, with police calling in for questioning family members who remain in Hong Kong.

Meanwhile, a colonial-era sedition law, part of a 1938 Crimes Ordinance unused for decades, has been revived as part of the national security law. A conviction carries a maximum two-year sentence.

What are the broader implications of the national security law on media, education and life in the city?

Since the law came into force in July 2020, books with potential to be deemed a national security risk were purged from schools and libraries, school curricula were changed to include national security education, and elections were overhauled to ensure only “patriots” could stand for office. A key protest slogan was also banned, and a succession of civic organizations, unions and activist groups folded.

A new national security office was set up with a dedicated police unit and security agents from the mainland have been empowered to operate openly in Hong Kong for the first time.

Press freedom groups have also pointed to a precipitous decline. Between 2021 and 2023, Hong Kong fell 60 places on a ranking of press freedoms. It now ranks 140 out of 180 countries and territories compared with 80 two years prior, according to Reporters without Borders (RSF). Two decades ago, RSF ranked Hong Kong 18th in the world for media freedoms.

Lai’s Apple Daily was forced to shutter after authorities froze the paper’s bank accounts following a June 2021 raid on its office, where they arrested several executives. Other media outlets also closed in the following months, including Stand News, which was also raided by national security police and saw executives arrested on sedition charges.

In Lai’s ongoing trial, the prosecution has alleged that articles published in Apple Daily violated the law.

Amid stringent border restrictions during the Covid-19 pandemic and the transformation of Hong Kong under the national security law, many Hong Kongers left the city, with official data showing the sharpest annual drop in population on record in 2022.

(L-R) Pro-democracy activists Eddie Chu, Gwyneth Ho, Leung Hoi-ching, Tiffany Yuen, Joshua Wong, Lester Shum and Agnes Chow campaign during primary elections in Hong Kong on July 12, 2020. - Pro-democracy parties in Hong Kong held primary polls on July 11 and 12 to choose candidates for upcoming legislative elections despite warnings from government officials that it may be in breach of a new security law imposed by China. (Photo by ISAAC LAWRENCE / AFP) (Photo by ISAAC LAWRENCE/AFP via Getty Images)

What do governments say about the law?

Hong Kong and mainland Chinese officials have praised the law as advancing “prosperity and stability” in the city following the 2019 protests, which at the time disrupted transport and business in the financial hub for multiple months. They’ve also said the law protects rights, freedoms, and the rule of law.

“The National Security Law is the major turning point in Hong Kong’s transition from chaos to order. Its effect in stabilizing the society is indisputable,” the city’s former Chief Executive Carrie Lam said following the first anniversary of the law in 2021.

Authorities have also regularly defended the law as in line with others internationally, arguing that “no country can or would turn a blind eye to threats to national security like the emergence of local terrorism and separatism seen in Hong Kong in 2019.”

Earlier this year, Hong Kong’s government said while press freedom is “respected and protected in Hong Kong, such freedom is not absolute.” It is “subject to restrictions” provided by law and necessary for “pursuing legitimate aims such as the protection of national security or public order.”

But Western governments say the law has slashed freedoms in Hong Kong and reduced its autonomy from the mainland, where rights groups have long pointed to arbitrary and politically motivated arrests and investigations and a conviction rate above 99%.

Hong Kong was promised 50 years of a high level of political autonomy after being handed over to China in 1997 after decades of British rule.

In response to the national security law’s imposition, the US revoked the special status that had for decades granted Hong Kong differential treatment in relation to mainland China. It also sanctioned dozens of mainland and Hong Kong officials including then-Chief Executive Lam and current leader John Lee, effectively blocking them from the international banking system.

The United Kingdom too decried the national security law, saying it rolled back freedoms and violated the terms of the original handover agreement. As a result, Britain created a new pathway to citizenship for Hong Kongers who hold a British National (Overseas) passport.

Two senior British judges last year resigned from Hong Kong’s highest court over the law. One of them, Robert Reed, who heads Britain’s top judicial body, accused the Hong Kong government of departing “from values of political freedom, and freedom of expression.”

In the wake of its imposition, the US, the UK and other countries also suspended their extradition agreements with Hong Kong over concerns about a decline in rule of law and perceptions of a shift in the territory’s relationship with the mainland.

During a regular review last year, United Nations Human Rights Committee experts wrote they were “deeply concerned” about the “overly broad interpretation of and arbitrary application” of the law and that it “overrides fundamental rights and freedoms.”

Hong Kong slammed the committee as accepting “false information and distorted narratives regardless of the truth.”

What will Hong Kong’s own security law mean for the city?

Even as Beijing’s national security law has had a sweeping impact, Hong Kong officials have said the city will implement its own new legislation in the coming year to plug “gaps.”

The law would cover additional offenses like treason and theft of state secrets and explicitly bar foreign political organizations from conducting political activities in the region and prohibit local political organizations from establishing ties with foreign ones.

Hong Kong is required to enact such rules under its mini constitution put in place in 1997. But doing so has been a contentious issue for decades, with a 2003 proposal bringing hundreds of thousands to the streets in protest.

During an annual address in October, Chief Executive Lee cited an assessment of the city from Xia Baolong, head of Beijing’s agency overseeing Hong Kong affairs, before reiterating his pledge to institute the law.

“’While Hong Kong may appear to be peaceful and calm, there are indeed undercurrents – the root causes for ‘chaos’ have not yet been eliminated, and the foundation of ‘orderly governance’ needs to be fortified,’” Lee said, quoting Xia.

“’We should pay particular attention to those anti‑China and destabilizing activities camouflaged in the name of human rights, freedom, democracy and livelihood,’” he said.

CNN’s Chris Lau and Kathleen Magramo contributed reporting.