The National Police Agency on Thursday unveiled a draft bill that would allow vehicles with a high level of autonomous features to run on public roads, with an eye toward implementing the legislation in the first half of 2020.

The bill to revise the nation’s road traffic law would enable travel for what the government classifies as level 3 autonomous vehicles. Such vehicles can allow drivers to shift their attention elsewhere and let the system drive, except for during emergencies and system glitches that would require them to take back control.

In the initial stage, the government may only allow the use of level 3 self-driving technology during highway traffic jams.

Autonomous driving technology is classified into five categories. Under the current law, only level 1 vehicles that have one of either automated steering, acceleration or braking features and level 2 cars that have more than one of those automated functions are allowed to travel on public roads.

Level 4 pertains to vehicles that can drive themselves under certain conditions without human input, even in emergencies, and level 5 cars have complete autonomy without any conditional requirements.

The draft bill would allow drivers of level 3 cars to talk on their mobile phones or watch TV, actions that are prohibited for those behind the wheel in conventional vehicles, as long as they can smoothly take back control of the car.

Actions such as working on a computer in the rear seat, sleeping or drinking alcohol would remain prohibited.

Self-driving vehicles would be banned from traveling on public roads unless they are equipped with travel data recorders. Drivers would also be required to save their driving data.

Drivers would be able to use level 3 autonomous features only when their vehicles fulfill conditions set by each automaker. The conditions, known as operational design domain, include weather situations, the type of roads traveled on, driving time and speed.

The government will solicit public comments starting Tuesday and continuing through Jan. 23 before submitting the bill to the ordinary Diet session next year.

In a country faced with a worsening labor shortage and the rapid aging of its population, hopes are high that self-driving technology can increase mobility for the elderly and resolve the shortage of drivers for logistics companies.

In Japan, automakers and taxi companies, among other businesses, have started testing autonomous driving vehicles on public roads.

But concerns remain about their safety, especially after a self-driving Uber car hit and killed a woman walking her bicycle outside a crosswalk in Tempe, Arizona, in March in what is believed to be the first fatal accident caused by an autonomous vehicle during testing.