Japanese drunk driving laws set a breath alcohol limit of 0.15 mg/L, punish the driver with up to five years in prison, and reach beyond the wheel to criminalize passengers, drink servers, and anyone who hands a drinker the keys. If an accident kills someone, the ceiling climbs to 20 years. The threshold is low enough that a single drink can put many people over it, and enforcement is strict.
The Two Levels of Drunk Driving
Japanese law splits alcohol-impaired driving into two offenses, and which one applies drives every penalty that follows.
Shuki-obi unten, or driving with alcohol in the system, is triggered the moment a breath test reads 0.15 mg/L or higher. It is a bright-line offense. Feeling fine and driving well do not matter if the number hits the threshold.
Sake-yoi unten, or intoxicated driving, is the more serious charge and covers a driver too impaired to operate a vehicle safely. Police assess it from observable signs: slurred speech, unsteady movement, inability to follow instructions. You can be charged with sake-yoi unten even if your breath reading comes in under 0.15 mg/L, because some people show heavy impairment at low concentrations.
Criminal Penalties for the Driver
The Road Traffic Act sets the standalone prison and fine ranges for both offenses, no accident required.
- Sake-yoi unten: up to five years in prison or a fine of up to 1,000,000 yen.
- Shuki-obi unten: up to three years in prison or a fine of up to 500,000 yen.1Japanese Law Translation. Road Traffic Act
These apply the moment an officer confirms impairment or a breath test exceeds the limit. Harsher charges under a separate statute take over if anyone is hurt.
Refusing the Breath Test
Refusing or interfering with a police breath test is itself a crime under Article 118-2 of the Road Traffic Act, carrying up to three months in prison or a fine of up to 500,000 yen.1Japanese Law Translation. Road Traffic Act The fine ceiling matches the shuki-obi penalty, so refusing buys you nothing. Officers can still charge sake-yoi unten from observable impairment alone.
Liability for Passengers, Drink Servers, and Car Lenders
This is where Japan departs sharply from most other countries. The criminal net extends to anyone who helped put a drunk person behind the wheel, and the penalties scale with the driver’s level of impairment.
Lending a Vehicle
Give your car to someone who has been drinking and you face the same penalty tier as the driver. If that driver ends up in sake-yoi condition, the person who provided the vehicle faces up to five years or 1,000,000 yen. For a shuki-obi driver, it is up to three years or 500,000 yen.1Japanese Law Translation. Road Traffic Act
Serving the Drinks
Supplying alcohol to someone you know will be driving is a separate offense. If the driver reaches sake-yoi levels, the server faces up to three years or 500,000 yen. For a shuki-obi driver, it drops to two years or 300,000 yen.1Japanese Law Translation. Road Traffic Act This reaches bartenders, restaurant staff, and friends at a party on the same terms.
Riding Along
Getting into the car as a passenger is also a crime. Riding with a sake-yoi driver carries up to three years or 500,000 yen. With a shuki-obi driver, it is up to two years or 300,000 yen.1Japanese Law Translation. Road Traffic Act The law assumes a sober enough passenger could have stopped the trip or found another way home.
When Someone Is Hurt or Killed
If a drunk driving incident causes injury or death, charging shifts to a separate statute, the Act on Punishment of Acts Inflicting Death or Injury on Others by Driving a Motor Vehicle, with far heavier ceilings.
Where alcohol made safe driving genuinely difficult, injuring someone brings up to 15 years in prison. Killing someone brings a minimum of one year and up to 20 years, the maximum definite prison term under Japan’s Penal Code.2Japanese Law Translation. Act on Punishment of Acts Inflicting Death or Injury on Others by Driving a Motor Vehicle, etc.3Japanese Law Translation. Penal Code
A lower tier covers drivers whose impairment was “likely to hinder safe driving” without clearly making it impossible. Injury here brings up to 12 years, death up to 15.2Japanese Law Translation. Act on Punishment of Acts Inflicting Death or Injury on Others by Driving a Motor Vehicle, etc.
A separate provision targets drivers who flee the scene or try to mask their intoxication, including drinking more after the crash to muddy the breath test. That evasion carries up to 12 years regardless of whether the victim lived.2Japanese Law Translation. Act on Punishment of Acts Inflicting Death or Injury on Others by Driving a Motor Vehicle, etc.
Even when the “dangerous driving” criteria are not met, negligent driving that causes death or injury carries up to seven years or 1,000,000 yen.2Japanese Law Translation. Act on Punishment of Acts Inflicting Death or Injury on Others by Driving a Motor Vehicle, etc. Alcohol in your system makes any leniency far less likely.
License Points and Suspension
Administrative sanctions run alongside the criminal case. Enough points means automatic suspension or revocation, with no discretionary hearing.
- Sake-yoi unten: 35 points, license revocation, three-year disqualification before you can reapply.
- Shuki-obi unten at 0.25 mg/L or higher: 25 points, revocation, two-year disqualification.
- Shuki-obi unten between 0.15 and 0.25 mg/L: 13 points and a 90-day suspension.
A clean record starts at zero, and most minor violations add one or two points.4National Police Agency. Eradication of Drinking and Driving Even the lowest drunk driving tier erases years of clean history in a single stop.
Insurance After a Conviction
A drunk driving conviction splits insurance coverage in a way that hurts the driver and preserves the victim’s claims.
Japan’s compulsory automobile liability insurance, known as CALI or jibaiseki hoken, keeps paying victims of accidents caused by drunk drivers. Payouts are only reduced for gross negligence by the victim, not by the drunk driver’s conduct.5Ministry of Land, Infrastructure, Transport and Tourism. Overview of Compulsory Automobile Liability Insurance and Mutual Aid CALI only covers bodily injury, however, not property damage.
Voluntary auto policies, which most drivers carry for broader coverage, typically exclude the drunk driver’s own claims. Both the driver’s medical expenses and damage to the driver’s own vehicle are voided when the insured was driving under the influence.6General Insurance Rating Organization of Japan. Automobile Insurance in Japan 2024 Hospital bills and car repairs come out of your pocket, on top of the criminal fines.
If You Are a Foreign National
Foreign residents carry an extra layer of risk: a conviction can end your ability to stay in Japan. The Immigration Control and Refugee Recognition Act permits deportation of any foreign national sentenced to imprisonment exceeding one year.7Japanese Law Translation. Immigration Control and Refugee Recognition Act A suspended sentence generally shields you, but actual prison time for a serious drunk driving offense, particularly sake-yoi unten with its five-year ceiling, puts deportation on the table.
Causing an accident raises the stakes further. Dangerous driving causing death or injury is specifically named as a crime that can bar entry to Japan for five years after the sentence becomes final, even if you leave the country before the case ends.8Embassy of Japan in New Zealand. Criminal Record and Entry into Japan The immigration consequences flow from the criminal conviction without a separate proceeding.
Drunk driving is not a standalone ground for visa revocation, but a conviction combined with a prison sentence triggers the general criminal deportation provisions. A short-term visitor driving on an international permit faces the same Road Traffic Act penalties as a resident.
Bicycles and E-Scooters
The Road Traffic Act applies to all vehicles on public roads, which pulls in bicycles and the electric kick scooters classified as specified small motorized bicycles.
A November 2024 amendment set a specific breath alcohol threshold of 0.15 mg/L for cyclists, matching the limit for cars. Before the change, drunk cycling was illegal but rarely enforced because officers had no numerical standard to apply. Cyclists caught over the limit now face the same shuki-obi criminal penalties as motorists: up to three years in prison or a 500,000 yen fine.1Japanese Law Translation. Road Traffic Act
There is a second consequence that catches people off guard. If you hold a Japanese driver’s license and are caught cycling drunk, police can suspend that license under the same administrative framework used for dangerous drivers, even though you were not in a car.
E-scooters sit under the same prohibition, and enforcement follows the same rules as for other motor vehicles.9National Police Agency. Traffic Rules for Specified Small Motorized Bicycles In Japan, there is no vehicle you can legally ride home after drinking.