Law and Enforcement


A dashcam in a Hong Kong taxi

A new police platform to capture dashcam evidence has a 20MB upload limit – enough for about three seconds of 4K video.

The police force will banjax its popular unofficial WhatsApp traffic vigilante hotline and replace it with a new dashcam evidence platform constrained by an upload limit of just 20 MB, police sources say.

The new reporting channel, PROVE (Public Reporting of Offences with Video Evidence), to be rolled out in June, is essentially a new front-end for the upgraded police non-emergency e-Reporting Centre, and aims to formalise the growing number of video evidence submissions from parking vigilantes and dashcams.

But with a 20MB file limit for both PROVE and the upgraded e-Reporting Centre, users will face complications in uploading their dashcam or smartphone footage. 20 MB is about three seconds of 4K HD video, a typical video format on a dashcam or smartphone. By comparison, a similar enforcement project in the UK allows up to 10 files of 1 GB each to be attached, around 500 times more capacity than the Hong Kong system.

Dilys Lo Shui-lun, a Traffic Branch superintendent who’s working on the PROVE launch, said the upgrade is at least was a step in the right direction. “We know 20 MB is not enough,” she says. “But we are constrained by government infrastructure.”

While police systems, including PROVE and the e-Reporting Centre, are developed by the IT Bureau, all such projects must conform to bandwidth and storage criteria set by the Office of the Government Chief Information Officer (OGCIO).

Lo says she hopes government infrastructure might be upgraded by next year to allow a more appropriate video submission file size limit. She says other departments face similar constraints – for example, the “catch all” 1823 government enquiry and complaint service has a 15MB video upload limit.

Sources say only a handful of recent submissions to the police WhatsApp line were under 20 MB, with an average size of around 125 MB more typical. The WhatsApp hotline, an unofficial initiative, had no published file size limit, with the app automatically compressing sent video as required. Such compressed video would not be admitted in court, but in many cases was sufficient enough to persuade offenders into accepting a ticket.

One step forward…

The upcoming launch of PROVE, while limited in its submission size, is at least more than a passing nod to the number of citizens wishing to submit video evidence for traffic offences.

Until recently, the only way to submit dashcam or traffic video evidence to police was to burn it onto CD-ROM or solid-state memory stick and deliver in person to traffic officers, where an official statement would be taken and signed. The process was onerous, time consuming and for many, simply not worth the effort. Meanwhile the e-Reporting Centre had a limit of just 5 MB per report, barely enough for one smartphone photo.

The popular dashcam reporting hotline will soon be axed as a new system is rolled out

In February this year, Senior Superintendent Michael Yip of the Hong Kong Island Traffic unit, who’d been receiving regular CD-ROM submissions from a small group of informants, decided to try a more flexible approach, setting up a personal phone with WhatsApp and WeChat and inviting existing sources to submit their Hong Kong Island dashcam footage through the social apps.

The unofficial WhatsApp channel – and police stress it’s not even unofficially a “WhatsApp” channel, merely a phone number informants can use to submit video evidence – was an immediate success: users uploaded 175 reports in the first month and 650 in the second as word spread, Yip says. Indeed, a number of traffic officers will be brought out of retirement to handle the extra cases and prosecutions, as the prosecutions are quite labour intensive, he says.

Informants shared offences such as parking in bus stops, dangerous driving, yellow-box offences, dangerous overtaking and unloading on double yellow lines.

The system is legally robust: officers use the video to prepare the case and contact alleged offenders. If the offenders accept the offence, a fixed penalty ticket is issued. If they contest the reports, the cases are passed for detailed investigation the same as any other traffic case, with the informant then required to make a written and signed statement, deliver CD-ROMs of the original uncompressed unedited video evidence and even appear in court if it goes that far.

But few of the WhatsApp cases have been contested, according to police.

“Video evidence is very powerful,” says Hong Kong’s top traffic cop, Chief Superintendent Martin Cadman. “Previously if someone makes a complaint, they say a driver cut me up, or the bus driver was driving dangerously, you need to get those people in, to get their version of events, to take statements. With the video, it usually tells us everything we need to know.”

But according to Cadman, there’s a number of problems with the social media or WhatsApp approach, not least that the force doesn’t have official permission to use the apps for law enforcement purposes. “If we develop the WhatsApp platform, it’s being used without WhatsApp’s express permission,” he says.

In fact, WhatsApp owner Facebook shut down 10 police violence hotline accounts last September after just three days’ operation, as the accounts didn’t meet the app’s terms of service.

But this aside, and noting that WeChat has no such issue, Cadman says a social media channel complicates the proper storage and handling of digital evidence. While they work well enough for a small group of trusted informants opening case files with compressed video footage, the WhatsApp or WeChat environments are not robust enough to be rolled out as law enforcement to the general public. The social media approach requires a lot of manual labour to move and store the evidence – and in cases where the video footage is contested by the offender, informants will still need to provide the force with a physical CD-ROM or other copy of the footage, along with a written statement. “We can handle 700 cases a month this way,” says Yip. “But we couldn’t handle 7,000.”

Cadman says PROVE, and the associated upgraded e-Reporting centre, will supersede all such social channels. “The force wants to have a centralised platform so that all digital evidence can be brought in, kept securely, disposed of securely, and all of that can be automated,” he says. “If it’s our own platform, we can build in the safeguards we need  for handling evidence and ensuring timelines and case management guidelines are met.”

Hong Kong’s legal system precludes smarter set-ups such as are used in the US and UK, says Cadman, whereby online submissions can act as an official signed statement. Cadman points to Operation SNAP in Wales, or Extra Eyes in Essex as two successful initiatives where dashcam footage can be shared with police and can result in prosecutions.


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