Among the many powers permitting the Chief Executive to exercise upon invoking the ordinance, it also include arrests, property seizures, deportation, control of the ports and transportation, and censorship.

Their grievances lay in the fact that the average Chinese port worker's monthly income was insufficient to support his family while his Caucasian counterparts, who earned several times more, had been granted 15% wage rise.

The Emergency Regulations Ordinance was passed by the colonial government that year – enacted in a single day – to combat the strikes, which paralysed the ports.

[7] The Government invoked the emergency law for several times in the early 20th century, including: in 1925 to order a clampdown on Canton–Hong Kong strike,[8] in 1929 to seize water supply during a drought, in 1932 to ban selling of food by hawkers following cholera outbreak in China, in 1935 to prohibit horses leaving New Territories and consuming grass amidst case of mule contracting rabies.

[9] After the end of World War II, immigrants from China swamped Hong Kong and issues of illegal trafficking hit the city.

In 1954, Colonial Office in London asked Hong Kong to repeal some articles deemed too powerful in the Emergency (Principal) Regulations.

[19] The invocations of emergency law was generally accepted by the citizens as the riots worsened with explosives harming innocents, but the perpetrating leftists and supporters were angered.

[23] Regulations were made to control the use of oil and motor fuel, to limit advertising displays and floodlighting, and to impose summer time.

[29] On separate grounds it also declared all the substantive sections of the PFCR excepting that prohibiting the use of masks at an unlawful assembly inconsistent with the Basic Law and the Bill of Rights, and therefore of no effect.

On 31 July 2020, Chief Executive Carrie Lam said she would invoke the Emergency Regulations Ordinance to postpone the 2020 Legislative Council election for a whole year, citing the resurgence of the COVID-19 cases.

The decision came after Xi Jinping, General Secretary of Chinese Communist Party, ordered the Hong Kong Government to halt the COVID surge by all means, despite saying a week ago that the postponement is not needed.

Accordingly, we shall grant an interim temporary suspension order to postpone the coming into operation of the declarations of invalidity for a period of 7 days up to the end of 29 November 2019, with liberty to apply.