How alcohol affects driving abilities

How alcohol affects driving abilities

In 2012, alcohol was the main reason. Already the consumption of small amounts of alcohol affects the ability to drive. The 0.5-percent reduction in traffic accidents 40 dead, 400 heavy limits take into account results from accident research. From this value increases the risk for and 1299 lightly injured. The typical pattern of traffic accidents clearly. But even at lower alcohol levels than 0.5 per thousand, severe alcoholic accidents are likely to impair driving-relevant abilities. 

General look

Insurers can demand cost-sharing in the case of fallible drivers (recourse), and from 2014, the motor vehicle liability insurance must take recourse to the person who caused the accident. In particular, in accidents in which people are injured, the financial demands can be very high.

Even those under the influence of alcohol, illegal drugs or drugs, motorless vehicles such as a bicycle or a wagon steers, can be forfeited.

Alcohol. Breathing controls in road traffic are permitted without suspicion and can be performed by the police at any time and anywhere. Blood tests are only carried out at the request of the vehicle driver or the driver or in a breath test with difficult to interpret result.

Drugs. If one of the following substances is detected in the blood, the inability to drive is considered proven:

  • – Cannabis (THC)
  • – heroin or morphine
  • – Cocaine
  • – amphetamine
  • – methamphetamine
  • – MDEA or MDMA (Ecstasy)

For other substances which may affect the driving ability, the judge and the driving license withdrawal certificate are based

Listen to a report on the principle of three pillars. Even the (semi) legal status of new substances offers no protection against legal consequences.

The three-pillar principle

The assessment of the driving ability of persons who have steered a vehicle under the possible influence of psychotropic substances is based on the so-called “three-pillar principle”.

1. Observations in the police protocol, testimonies, etc.

2. Medical examination

3. Forensic toxicological analyzes


According to the Road Traffic Act, the use of medicines is not fundamentally incompatible with participation in transport. But some drugs limit the ability to drive and you make a punishable, if you steer a means of transport under their influence. Since there are no quick tests and recognized limits, the three-pillar principle also applies when assessing the ability to drive under the influence of medication. In this assessment, it is irrelevant whether the drug is available by prescription or free. Even herbal remedies can lead to a disability.

The power reserve

Many alcoholized vehicle drivers have the impression that they are “able to drive” because they want their driving skills to be particularly good or to drive with particular care. Alcoholized persons often underestimate the influence of alcohol on their performance and often do not know that the so-called “power reserve” is significantly limited even after the consumption of low alcohol.

The brain works in two stages for many activities: Automatisms – everything that is practiced and trained – are mastered with the basic services. If, however, something unforeseen happens, the power reserve is required for the right reaction. This is the case, for example, when someone unexpectedly runs into the street. The correct assessment of the situation and the corresponding rapid response require the power reserve of the brain.

Up to about 0.5 per thousand have experienced motorists in general. The power reserve is only sufficient enough when one is able to respond and react appropriately in critical situations. From this value, however, the power reserve is so severely impaired that no adequate response is possible in difficult situations. From about 1 per thousand in addition, the basic performance is affected – it is no longer up to the usual situations.

Newcomers already need their power reserves for everyday traffic situations because their reactions have not yet been automated. With them very little alcohol can lead to serious performance deficits. But even for experienced drivers, the rule is: Only with 0.0 per thousand, one is sure that alcohol does not affect the performance in road traffic! But not only alcohol, but other psychoactive substances (illegal drugs, sleeping pills and sedatives, etc.) and other factors (illness, stress, fatigue, etc.) can reduce the reserve of performance.

Driving ability is the individual’s current mental and physical ability to safely drive a motor vehicle in traffic. The inability to drive is in principle temporary (for example as a result of alcohol, narcotic or pharmaceutical consumption, tiredness); However, in special cases it may be a symptom of a lack of fitness to drive, for example an addiction to narcotics.