Tailgating (Aori-unten) in Japan: How to Stay Safe on the Expressway

Driving in Japan is generally considered to be a safe, polite, and orderly experience. International drivers often remark on how courteous Japanese drivers are, from the strict adherence to traffic signals to the famous “thank you” hazard light flash. However, like any country, Japan has its share of aggressive drivers. In recent years, a specific type of aggressive driving known as *aori-unten* (あおり運転), or dangerous tailgating and road rage, has become a major social issue. High-profile incidents on the expressways have led to strict new laws and severe penalties. For tourists renting a car and taking to the Japanese highways, understanding what *aori-unten* is, how to avoid triggering it, and what to do if you become a target is crucial for a safe and stress-free road trip. This guide will provide you with practical advice on dealing with aggressive drivers on Japanese expressways.

Understanding Aori-unten (Dangerous Driving)

The term *aori-unten* literally translates to “fanning driving” or “instigating driving.” It is not just simply following slightly too closely; it refers to a pattern of aggressive, intimidating behavior designed to harass another driver or force them to yield.

What Constitutes Aori-unten?

According to Japanese traffic law, which was severely tightened in 2020 specifically to combat this issue, *aori-unten* encompasses several specific dangerous behaviors. The most common is extreme tailgating—driving aggressively close to the rear bumper of the car ahead, often while flashing high beams or honking the horn repeatedly.

However, the legal definition also includes other forms of harassment on the expressway. This includes suddenly pulling in front of another car and slamming on the brakes (brake-checking), aggressively weaving between lanes to intimidate, or forcefully squeezing another vehicle toward the shoulder or central reservation. In the most extreme cases, the aggressive driver may attempt to force the victim’s car to a complete stop on the highway, which is incredibly dangerous. Recognizing these behaviors early is the first step in protecting yourself. For a broader overview of highway rules, you can read Unspoken Rules of Japanese Highways: The “Thank You” Hazard Lights and Driving Etiquette.

The Strict Penalties and Dashcams

The Japanese government takes *aori-unten* extremely seriously. Following several tragic accidents caused by road rage, the Road Traffic Act was amended to create specific, harsh penalties for “obstructive driving.”

If a driver is caught engaging in *aori-unten*, they can face up to three years in prison or a fine of up to 500,000 yen, and their driver’s license will be immediately revoked. If their actions cause an accident resulting in injury or death, the penalties are significantly higher. Because of this crackdown, almost all rental cars and domestic vehicles in Japan are now equipped with forward and rear-facing dashcams (drive recorders). The footage from these cameras is routinely used by the police to prosecute aggressive drivers. If you are renting a car, confirm with the agency that a dashcam is installed; it is your best objective witness.

How to Avoid Triggering Aggressive Drivers

While you cannot control the behavior of other drivers, you can adjust your own driving habits to minimize the chances of irritating someone prone to road rage. On Japanese expressways, there is a specific etiquette regarding lane usage that international drivers must understand.

The Golden Rule: Keep Left

The most common trigger for *aori-unten* on a Japanese expressway is a vehicle cruising slowly in the passing lane. In Japan, you drive on the left side of the road. The far-left lane is for cruising, and the right lane (or lanes) is strictly for passing.

Many international drivers make the mistake of moving into the right lane and staying there because it feels less cluttered with merging traffic. However, under Japanese law, you must return to the left lane as soon as you have completed your overtaking maneuver. Cruising continuously in the passing lane is not only illegal (you can be ticketed for “failure to keep to the designated lane”), but it infuriates fast-moving drivers who want to pass. If you see a car approaching rapidly from behind while you are in the right lane, immediately activate your left turn signal and move over when it is safe to do so.

Proper Merging and Speed Matching

Another common flashpoint occurs at junctions or when entering the expressway from a Service Area (SA) or Parking Area (PA). When merging onto the main highway, it is your responsibility to match the speed of the traffic already on the road.

Do not attempt to merge at a slow speed and expect the highway traffic to brake for you. Accelerate briskly on the on-ramp, use your turn signal early, and merge smoothly. Similarly, if you are driving on the highway and see a car trying to merge from an on-ramp, it is common courtesy in Japan to briefly move to the right lane (if safe) or adjust your speed slightly to allow them in. Failing to merge smoothly or cutting someone off can trigger a road rage incident. If you are unsure about the speed limits, you can review Highway Speed Limits in Japan: What You Need to Know Before Driving.

What to Do If You Are Targeted

Despite your best efforts to drive politely and follow the rules, you might still encounter an aggressive driver. If you find yourself being severely tailgated or harassed (experiencing *aori-unten*), it is critical that you remain calm and prioritize your safety.

Do Not Engage or React

The absolute most important rule when dealing with road rage is to not engage with the aggressor. Do not make eye contact, do not make rude hand gestures, and do not shout back, even from inside your closed car.

Do not attempt to “teach them a lesson” by tapping your brakes (brake-checking) or deliberately slowing down. These actions will only escalate the situation and put you in extreme danger, especially at highway speeds. Your only goal is to de-escalate the situation and separate your vehicle from theirs. Keep your hands on the steering wheel, keep your eyes focused on the road ahead, and maintain a steady, predictable speed.

Safely Yield the Right of Way

If you are being tailgated in the passing lane, the solution is simple: turn on your left indicator and move into the left lane as soon as it is safe to do so. Let the aggressive driver pass.

If you are already in the left lane and the driver continues to tailgate you, maintain a steady speed. Do not speed up to appease them, as you might get caught by a speed camera. If the harassment continues, look for the next safe opportunity to pull off the main road. The best option is to exit the highway entirely or pull into the nearest Service Area (SA) or Parking Area (PA). Often, simply changing your route or taking a break is enough to shake off an aggressive driver. You can find safe places to stop by reading Navigating Japanese Highway Service Area Parking: A Beginner’s Guide.

Handling Extreme Situations on the Expressway

In rare and extreme cases, an aggressive driver may not be satisfied with simply passing you. They may attempt to force you to pull over or stop on the expressway itself. This is an incredibly dangerous situation that requires immediate, specific action.

Never Stop on the Main Highway

Under no circumstances should you stop your vehicle on the main driving lanes or the shoulder of the expressway to confront an aggressive driver. Stopping on a high-speed road is a recipe for a catastrophic rear-end collision involving uninvolved vehicles.

If the aggressor pulls in front of you and begins braking heavily to force you to stop, do everything in your power to safely maneuver around them and keep moving. If you are forced to a complete stop against your will, immediately turn on your hazard lights. Do not unlock your doors and do not roll down your windows. If the aggressive driver approaches your car, remain inside, ensure the doors are locked, and ignore their demands. Your car is your safest armor in this situation.

Call for Help Immediately

If you are forced to stop, or if you feel you are in immediate physical danger while driving, you must call for help. In Japan, the emergency number for the police is 110.

If you are driving with a passenger, have them call 110 immediately. If you are alone, you are legally permitted to use your mobile phone in an emergency situation to call the police, even while driving, though it is safer to use a hands-free system or pull into a Service Area first if possible. When you connect with the police, state your location as clearly as possible (look for the green kilometer marker posts on the side of the highway) and explain that you are the victim of *aori-unten*. Many dispatchers can handle basic English, or they will transfer you to an interpreter service. For more details on emergency procedures, see Emergency on a Japanese Highway: What to Do and How to Call for Help (JAF).

Conclusion

While the term *aori-unten* sounds intimidating, it is important to remember that the vast majority of drivers in Japan are incredibly courteous and rule-abiding. Road rage incidents, while highly publicized, are relatively rare.

By understanding the rules of the Japanese expressway—specifically the strict adherence to the “keep left” rule—you can easily avoid the most common triggers for aggressive driving. If you do encounter a frustrated or dangerous driver, your best defense is a calm demeanor and a refusal to engage. Let them pass, utilize the excellent network of Service Areas to take a break, and rely on the safety of your locked rental car and the police (110) if a situation ever escalates. Armed with this knowledge, you can confidently navigate the expressways and enjoy the beautiful scenery and excellent facilities that a Japanese road trip has to offer.