US congressional representatives announced legislation on Tuesday calling for a ban on sales of riot control equipment to Hong Kong law enforcement services, as unrest in the city entered its fourth month. If passed, the bill would prohibit US companies from exporting so-called non-lethal crowd control items like tear gas, as well as defence articles and services, to Hong Kong, where the local police force is facing growing criticism of its response to protests. Since mass demonstrations began in June over a proposed extradition bill, violent clashes involving police, protesters and counterprotesters have hospitalised dozens of people. After last week’s announcement that the bill was to be officially withdrawn, the protesters’ remaining four demands include an independent inquiry into the use of police force – a call that city leaders continue to reject. Titled the PROTECT Hong Kong Act, Tuesday’s bill is sponsored by Representatives James McGovern, Democrat of Massachusetts, Christopher Smith, Republican of New Jersey, and Ro Khanna, Democrat of California. The ban would take effect 30 days after the legislation’s enactment. As well as barring defence-related sales to Hong Kong, the new law would also require the Secretary of State to issue a report to Congress detailing all the defence articles and munition items that had been exported to the city over the five years leading up to the bill’s date of enactment. Smith said that “Congress must stop the flow of these exports to the government of Hong Kong” until it became clear that American products were not being used “to repress the free people of Hong Kong”. “This legislation does that,” he said. “America ought to recognise the human rights and dignity of all people,” said McGovern, who co-chairs the Tom Lantos Human Rights Commission alongside Smith. “And that means we ought not to allow American companies to sell this equipment to foreign governments when we see evidence that it is being used for immoral and unjust purposes.” Last month, the United Nations’ Office of the High Commissioner for Human Rights said it had reviewed credible evidence that law enforcement officials in Hong Kong had employed non-lethal weapons “in ways that are prohibited by international norms and standards”. Officers had been seen “firing tear gas canisters into crowded, enclosed areas and directly at individual protesters on multiple occasions, creating a considerable risk of death or serious injury”, the UN office said, calling for an immediate investigation into the incidents. Tuesday’s bill enters Congress, which returned from its summer break this week, several months after the British government suspended its own exports of crowd-control equipment to Hong Kong. Britain suspends exports of tear gas and rubber bullets to Hong Kong Announced in June, the ban would remain in place until concerns about human rights and fundamental freedoms in the city were addressed, the then foreign secretary Jeremy Hunt said. In July, a resolution was passed by the European parliament calling on member states to impose “appropriate export control mechanisms to deny China, and in particular Hong Kong, access to technologies used to violate basic rights”. Only a small fraction of bills introduced by US lawmakers end up being signed into law by the president; and even if Tuesday’s legislation successfully passes through the many Congressional procedural hurdles, it would probably be a matter of months before it reached US President Donald Trump’s desk. Meanwhile, the Hong Kong police force already seems to be setting its sights on other suppliers. In late August, the force confirmed it was pivoting away from European vendors and was purchasing anti-riot protective gear from a mainland manufacturer. Personal armour procured from the supplier cost around US$420 per suit and was the same type as that used by police on the mainland, according to a Hong Kong police source. Concurrently, the mainland is also expected to step up production of tear gas in the face of rising demand both within and beyond its borders, though Hong Kong is not yet believed to be an export destination. To date, Hong Kong authorities have used upwards of 1,800 rounds of tear gas since June, according to police figures. A recent Buzzfeed News investigation into one American tear gas manufacturer whose canisters have been deployed by Hong Kong law enforcement found that low-paid employees were handling hazardous materials with few safety precautions. UN human rights body takes aim at Hong Kong police Pennsylvania-based Nonlethal Technologies, which has also supplied riot-control equipment to a number of Middle Eastern governments during the Arab spring, did not respond to a request for comment on Tuesday’s legislation. Concern among US lawmakers about exports of crowd-control technology to Hong Kong was not limited to the House. On Tuesday, a bipartisan group of 10 senators wrote to the US administration calling for an investigation into whether the country’s export control regime allowed people in the US “to inappropriately export police equipment to Hong Kong, which may be used to suppress legitimate civil dissent”. Sent to Secretary of State Mike Pompeo and Secretary of Commerce Wilbur Ross, the letter also called on the administration to examine whether hi-tech exports from the US to Hong Kong were at risk of being illicitly acquired by the Chinese government.