Shanghai traffic police have announced that they will now accept dash-mounted videos from people that show evidence of a traffic violation.

However, in order for the police to press charges and issue fines based on the evidence, certain conditions need to be met.

First, the violation must have occurred within three days of reporting it. Secondly, the video must feature road signs or other distinguishing features that clearly show where the violation occurred. Finally, videos cannot be longer than 60 seconds, and 100MB in size.

Shanghai traffic police say they will investigate each submission within 15 business days. City residents who make a submission can follow the complaints progress online.

Although the Shanghai Public Security Bureau was initially hesitant to adopt dash-cam evidence, other jurisdictions in China have openly embraced it. In May 2014, Shenzhen authorized the use of dash cams in its ambulances to help prosecute drivers who fail to yield right-of-way to ambulances.

Dash cams have become increasingly popular in China as a way for drivers to protect themselves against being extorted in “broken vase” scams. The cameras have also been important in capturing road rage incidents.

Want to make the streets of Shanghai safer? You can submit a video here. For now, services are only available in Chinese.