On 6 September, the biggest protests in the course of the 2019-20 Hong Kong protests since 1 July occurred in the city. The fresh protests were in a large part due to the day having been the scheduled election day for the Legislative Council; on 31 July, the Hong Kong government had the elections postponed by a year, citing the COVID-19 pandemic, a justification that was widely doubted. The unauthorized protests resulted in nearly 300 arrests, one of them on suspected violation of the national security law, and brought the total number of arrests during the entire protests since June 2019 to above 10,000.

The national security law continued to exert a major influence both within Hong Kong and internationally, for its perceived devastating effect on the "One country, two systems" principle forming the foundation of governance in the city, even though Hong Kong and mainland government officials had asserted that it had rather acted as a stabilizer. The state visit of Chinese Foreign Minister Wang Yi to five European countries, which concluded on 1 September, was accompanied by protests at each stop, and the topic of Hong Kong was brought up by several of his hosts. The lack of substantial news of twelve detainees who had been caught by Chinese authorities on 23 August in a botched attempt to flee from Hong Kong to Taiwan met with broad condemnation, despite assurances by China that the detained did have legal support. Other news from throughout the month, from disparate areas, suggested that large parts of the population of the city had either rejected the local government's assurances that the national security law would only affect a small minority of the population, or saw the international negative responses and sanctions which were triggered by the law as exacting a heavy and lasting toll on the economy of the city, on top of the just recently calmed third wave of the COVID-19 pandemic.

Events 1 September International response: Germany German Foreign Minister Heiko Maas met with China's Foreign Minister Wang Yi as the final stop of Wang's European tour on bilateral talks. Before the meeting, Hong Kong activist Nathan Law along with tens of protesters waving Uighurs' flags and "Stand with Hong Kong" signs, staged a protest against China's visit. Law also presented a letter to German officials on August 30, imploring Germany and other European countries to "go further" in their "reassessment of policy towards China". In the meeting with Wang, Maas called for the withdrawal of China's national security law in Hong Kong, claiming that Germany wished to see "the principle of 'one country, two systems' to be fully applied". Maas also brought up the now delayed Hong Kong legislative election, calling for the election to take place "quickly and unhindered".

2 September

Nathan Law urges the West to take action The day after protesting Wang Yi's presence in Germany, Nathan Law held a 10-minute interview with German news agency Deutsche Welle. In the interview Nathan Law called on Germany and all democratic countries to form a united front of democracy to defend against Communist China's "infiltration". Law urged every country to interact with China with dignity, and not to shy away from bringing up human rights issues.

National security law effect: British expat teachers in Hong Kong consider resigning In interviews with British newspaper Daily Telegraph, British nationals teaching in Hong Kong's international K-12 schools expressed frustration and confusion, mulling resignation while reexamining their lessons as the new school year begins. With the new national security law that intends to criminalize anything "the authorities deem to be terrorism, secession, subversion, or foreign collusion", many teachers were told by their school administrators to maintain a neutral presence on social media and in real life. In addition, they were reminded that their students' families may have ties with China or may be Hong Kong government officials who decry the year-long pro-democracy protests. One teacher said that she had considered canceling a unit on peaceful protests, in which Rosa Parks from the United States' civil rights movements in the 1960s, would have been used as an example. Another teacher reported to have sought advice on how to present the 1989 Tiananmen Square protests and massacre factually without stepping over the new red line. 48% of protest-related arrestees are under 18 years of age.

National security law effect: academic and speech freedom threatened in a new school year Many incidents, large and small, have occurred since the enactment of the Hong Kong national security law that affect the education sector from K-12 to higher education. For example, days after the enactment of the law, "sensitive" books were removed from libraries and students were banned from expressing their political views or participate in political protests. Later in July, tenured Hong Kong University associate law professor Benny Tai was fired by the university's governing council and against the recommendation of the university's senate, for his involvement in the 2014 Umbrella movement and his anti-China stance. At the same time, social worker, lawmaker, and pro-democracy activist Shiu Ka-chun was told that he will no longer be teaching at Hong Kong Baptist University (HKBU) due to him being too "high profile". Many university campus newspaper journalists are confused if "covering a story" could be seen as "promoting" and therefore drawing national security concerns, leading to censoring their own work due to fear. At the secondary level, concerned groups of teachers and educators urged Education Secretary Kevin Yeung in an open letter recently to not censor textbook contents and "hinder students from independent thinking and stifle free thought" after several textbook publishers "revised content in eight sets of Liberal Studies textbooks following a voluntary screening conducted by the Education Bureau". To start off the school year, on September 1, a 16-year-old boy from Heung To High School was suspended for a week for his “Liberate Hong Kong” avatar icon, a phrase deemed “seditious” by the Hong Kong Education Bureau under the new national security law. The student complied with the school's request and removed such photo from his profile picture within minutes. Nonetheless, the school demanded that the student withdraw for damaging the school's reputation. If the student chose to stay he would have two “demerits” listed on his permanent record. After the one-week suspension the student told reporters that Heung To administration threatened expulsion if he were found participating in any anti-government political events in any shape and form. A Heung To teacher told reporters that the consequence was really lenient and that the student could find another school if he were unhappy with the school or the punishment. Finally, citing national security law, Heung To reported this incident to the Education Bureau for further investigation and evaluation. In a response to the Stand News, Education Bureau stated that school campuses are not the place for political activism and all schools can do a better job ameliorating the anti-government mindset common in youth.

3 September

Hong Kong-born Japanese journalist arrested by Hong Kong Police Awaiting confirmation from the Japanese embassy, Japanese newspaper The Sankei News reported that one of its staff, a male photographer, could be one of the 15 arrested by police on 31 August in the Prince Edward station attack one-year commemoration protest. The journalist reportedly had been seen at numerous protests over the past year, and was once arrested at the Siege of the Hong Kong Polytechnic University. Police later stated that the journalist, a Hong Kong born Japanese citizen, had been working as a freelance reporter at the time when he was again arrested. They further stated that he had not told the police at the scene about him being a reporter and that police had not been able find evidence in his belongings to prove him to be one. He was arrested for illegal possession of an airsoft gun, and released on bail by 3 September pending further investigation.

4 September

International response: United Nations A 14-page report made by the United Nations dated September 1 and made available today decried Beijing's newly enacted Hong Kong national security law as being in breach of international legal obligations. The report listed out the committee's deep concerns over the ambiguous language in the national security law and the violations of Universal Declaration of Human Rights (UDHR) and the International Covenant on Civil and Political Rights (ICCPR). The committee report concluded with six actionable requests to China and Hong Kong governments, such as: explain how the legislation is compatible with the government's "obligations under articles 2, 14, 15, 17, 19, 20, 21, 22 of the ICCPR and articles 11, 12, 19 and 20 of the UDHR and how it may remediate the aforementioned inconsistencies with international human rights standards enshrined in the Act" and "provide information on how your Government intends to enforce the extra-territorial jurisdiction of the legislation as enshrined in articles 36, 37, 38, and 55 to ensure compatibility with the ICCPR."

5 September

Apple's statement on Hong Kong iCloud user data storage Days after Beijing passed the Hong Kong national security law, international tech giants such as Google, Twitter, Microsoft and Facebook have already declared that they would not comply with Hong Kong or mainland Chinese authorities' requests for user data. However, with its China data center being state-run, tech company Apple has not made any statements to the public until today. "iCloud data for Hong Kong users is stored on US servers," Apple stated, and therefore "any request from Hong Kong authorities to hand over the data must first be approved by the U.S. Justice Department and a warrant must be issued by a U.S. federal judge before handing it over." Apple also further released some statistics relating to user data request: "Hong Kong authorities made 604 requests for device information, 310 requests for financial data, and 10 requests for user account data during 2019." Data from July 2020, since the enactment of the national security law, will be released in the next transparency report.

6 September

The 12 detainees are denied lawyers; may be sentenced to prison for life