The city held its first National Security Education Day after the national security law had come into force. Chief Executive Carrie Lam emphasized that the law had helped Hong Kong to emerge from the "dark violence" of the 2019–2020 Hong Kong protests. National Security Committee Adviser Luo Huining also gave a speech. Even very young children were photographed handling toy weapons, which drew criticism.

Journalist Bao Choy was convicted of having made false statements in order to obtain public records about car licensing plates. Choy had requested these for a documentation about the 2019 Yuen Long attack which public broadcaster RTHK aired in 2020. The conviction was seen by journalist groups as a sign of shrinking press freedom in the city. Proclamations by police chief Chris Tang about the government intending to target "fake news" were considered by some to be an ill-defined notion and pointing in the same direction.

Seven veteran pro-democracy activists were sentenced for organizing and participating in a large unauthorized march on August 18, 2019. There were also a number of other convictions in relation to the protests of 2019.

As the government took steps to implement the 2021 Hong Kong electoral changes enacted by the National People's Congress, pro-establishment politicians floated the idea of making blank voting illegal, although this was considered either impractical or otherwise problematic by others.

1 April

Pro-democracy figures convicted for 18 August rally Jimmy Lai, Lee Cheuk-yan, Margaret Ng, Leung Kwok-hung, Cyd Ho, Albert Ho, and Martin Lee were found guilty of "organizing and participating in an unauthorized assembly", after being arrested for their participation in an unauthorized rally on 18 August 2019, which was also participated by some 1.7 million citizens.

Responses At a White House press briefing, Press Secretary Jen Psaki said that the ruling once again showed that Beijing was eroding Hong Kong's freedoms and not fulfilling its international obligations under the Sino-British Joint Declaration.

U.S. State Department criticized the ruling. Spokesperson of UN Secretary-General Antonio Guterres said that people should have the right to gather peacefully.

Deputy Commissioner of police said Hongkongers should not test the red line of the National Security Law Deputy Commissioner of Hong Kong Police Oscar Kwok was interviewed by Bloomberg. He did not respond positively to what specific behaviours violate the national security law. However, he said that Hongkongers should think about how to contribute to social harmony, peace and security, instead of 'trying the law' to test Hong Kong national security law's "red line".

3 April

Discussion over blank votes During interviews with the press on 4 and 5 April, Secretary for Justice, Teresa Cheng, and Secretary for Constitutional and Mainland Affairs, Erick Tsang, floated the idea of banning blank ballots in the 2021 Hong Kong legislative election. The 2021 Hong Kong electoral changes had made blank voting appear as a possible form of protest. Legal scholar Johannes Chan from the University of Hong Kong pointed to legal difficulties in banning voters from casting blank ballots. Pro-establishment lawmaker Paul Tse said that such a ban would not be necessary in his view, but he warned that appeals for others to cast blank votes may violate the national security law. Democratic Party chairman Lo Kin-hei was evasive about the question whether his party would encourage blank voting, pointing to his party not having decided yet whether to run in the elections; if it were to run, it "would sound strange if we encouraged people to cast blank votes", he said.

Hongkongers emigrate to UK during Easter holiday During the Easter holiday, Apple Daily inspected the Hong Kong International Airport and found that in the deserted departure hall, only the check-in counters for flights to the UK were crowded. Parents of Hong Kong residents who are preparing to immigrate to the UK stated that the political environment in Hong Kong was deteriorating. Under the circumstances of the national security law and the electoral reform, as well as the amendment proposed by the Security Bureau to amend the Immigration Ordinance, the Hong Kong government was to be granted the right to prevent Hong Kong people from leaving the country from 1 August. There were also international students who think that the pandemic situation in the UK had improved sufficiently for them to return to the local campus to attend classes.

Japanese telecommunications company KDDI considers moving data out of Hong Kong Japanese media reported that KDDI (mobile phone service brand au) was considering transferring the relevant information from Hong Kong back to Japan for safekeeping, in response to China's implementation of the National Intelligence Law in 2017 and the Hong Kong national security law. At present, the company's server in Hong Kong stores data of mobile phone users in Japan, including phone numbers and communication usage.

5 April

12 activists from the Mainland were handed over to Hong Kong after serving their sentences

Five of the Hong Kong activists who had completed their sentences in the Mainland and been handed over to Hong Kong appeared in Sha Tin Magistrates' Courts for their respective criminal cases after completing the quarantine. The five persons, Wong Wai-yin, Kok Tsz-lun, Cheung Chun-fu, Cheung Ming-yu and Yim Man-him, were taken to Sha Tin Magistrates' Courts by prison van. Wong was charged with manufacturing explosives in January last year, and the case was adjourned to be heard on the 3 May. Kok Tsz-lun was accused of rioting during protests in November 2019. His trial was adjourned to 5 May, awaiting referral to the District Court. Cheung Chun-fu, Cheung Ming-yu and Yim Man-him were accused of conspiring to illegally and maliciously harm police officers in December 2019; Cheung Chun-fu was also charged with possession of offensive weapons or tools suitable for illegal purposes. The five defendants did not apply for bail.

Patrick Nip: Improving Hong Kong electoral system must be interpreted with National Security Law Secretary for the Civil Service, Patrick Nip, stated that the improvement of Hong Kong's electoral system must be interpreted together with the Hong Kong national security law. Nip said on social networking sites that last week, he held a related commentary meeting with director-level civil servants of the administrative director grade, emphasizing that civil servants are an important part of the administrative organ. Any changes to the social system require their concerted efforts to promote. He also quoted some civil servants at the meeting saying that visiting the mainland more often would definitely help to gain a deeper understanding of the country's development.

7 April

Andy Li appears at the court on collusion charges

One of the 12 Hong Kong activists, Andy Li, a member of the Hong Kong Story, appeared in court for the first time after completing quarantine. The case was conducted in West Kowloon Magistrates' Courts, to which Li was escorted by a large police motorbike fleet. Barrister Lawrence Law and solicitor Trevor Chan represented Li. Chan refused to tell reporters how Li had instructed him; he said he was "definitely not a government-appointed lawyer" and was unwilling to answer questions about why Li's family did not know him or Law. Law had been suspended twice in 2005 and 2007 owing to complaints about misconduct.

Pro-democracy figures plead guilty for unauthorized 31 August rally Jimmy Lai, the founder of Next Digital, Lee Cheuk-yan, secretary-general of the Confederation of Trade Unions, and Yeung Sum, the former chairman of the Democratic Party, are accused of participating in an unauthorized rally, which was held on Hong Kong Island on 31 August 2019. They alleged that their parade was blocked for more than an hour. All three pleaded guilty. Lee said he had done "nothing wrong and history will absolve us". At the same time, he quoted political philosopher John Rawls's theory of fairness and John Stewart Mill's "On Freedom" and other works. He did not hesitate to test the law by himself or protest against the draconian law through peaceful civil disobedience, and was willing to accept legal and criminal responsibility. District Court judge Amanda Woodcock adjourned the case until 16 April after hearing the plea. Yeung and Lee were released on bail, during which Yeung had to surrender his travel documents, while Lai continued to be remanded due to the case.

Protester who was accidentally shot in melee sentenced to training center and given criminal record On 4 October 2019, around 200 protesters occupied roads in Yuen Long to protest against the government's enactment of the Prohibition on Face Covering Regulation. A plainclothes officer approached the scene. As he exited the car, someone attempted to snatch his gun. He was surrounded by an angry crowd, reportedly as he was believed to have bumped into a person. A 14-year-old boy was shot by him in the left thigh in the ensuing chaos. The police officer was subsequently beaten by protesters and had a petrol bomb thrown at him, after which he escaped and called for help on his phone, and from arriving police vans after having been hit by another Molotov cocktail. Fanling Magistrates' Court Magistrate Don So said at the trial of the boy that he had been influenced by online calls as well as the sentiments of the crowd, and that he considered to have deserved being hit. Citing the seriousness of the incident, the magistrate sentenced the boy to a training center and ordered him to receive a criminal record.

Nathan Law granted political asylum in the UK Former LegCo member Nathan Law posted on Facebook announcing that he had been granted political asylum in the UK. British Foreign Secretary Dominic Raab confirmed the news on Twitter on 8 April, stating that "the UK has a glorious history in providing protection to those in need." The Chinese Ministry of Foreign Affairs issued a warning on the next day that the United Kingdom had provided asylum for Law. The spokesman Zhao Lijian stated at a regular press conference that he "opposes any country, organization, or individual to shelter criminals in any way." He described the British side as a platform for Hong Kong independence elements and providing so-called asylum for wanted criminals. He described the act as a gross interference in Hong Kong's justice, contrary to international law and basic norms of international relations, and also against the rule of law principles that the British side had always advertised. He urged the British side should immediately correct its mistakes and stop interfering in Hong Kong affairs and China's internal affairs.

9 April

Prosecutors in Tong Ying-kit's case cited ancient examples In the first case of the Hong Kong national security law, the defendant Tong Ying-kit was charged with inciting others to commit secession and terrorist activities. The prosecution invited Lau Chi-pang, a professor in the Department of History of Lingnan University, as an expert witness to write a report. He described the defendant driving a motorcycle with a Liberate Hong Kong flag, just like a soldier in ancient times putting on a battle flag and riding a horse on the battlefield. The High Court held a hearing to determine whether to accept the report as evidence. The judge questioned that Article 20 of the national security law clearly listed three types of secession behaviors, and believed that historical analysis was not helpful in interpreting legal provisions. In the end, only part of the testimony was approved, and the part of ancient history was rejected.

13 April

Activist jailed for unauthorized anti-mask ban rally