Alcohol interlocks and drink driving rehabilitation in the European Union

Best practice and guidelines for Member States
Houwing, S.

In many European countries there is still a small group of hard core drink driving offenders that do not seem to be influenced by traditional countermeasures. This group accounts for 10% of all drink driving offenders, but are involved in two thirds of all alcohol-involved crashes. The introduction of an alcohol interlock programme seems to be an effective measure, as an alternative to ‘traditional’ measures such as fines and driving licence suspension.

Belgium, Denmark, Finland, France, The Netherlands, Poland and Sweden have already introduced alcohol interlock programmes for drink driving offenders. Furthermore, Austria has announced that it will introduce mandatory alcohol interlocks in 2017 after two successful trials in 2012 and 2013.

Based on the good experiences in these countries, as well as some of the pitfalls that have emerged, this report offers a set of practical guidelines to support authorities that want to introduce an alcohol interlock programme. The guidelines concern seven key areas, including good, pro-active communication between all stakeholders which is seen as crucial to success. The guidelines are summarised as follows.


  1. Alcohol interlock legislation needs to be well-grounded and clearly described in the legal system so that it can’t be disputed on legal grounds. As part of the legal foundation, special emphasis should be given to the relative position of the alcohol interlock programme when compared to other sanctions and measures.
  2. Before introduction of the legislation, information should be provided to all stakeholders concerning the contents and the purpose of the legislation and a public awareness plan should be created that sufficiently informs all drivers of the content of the new legislation and the implications for offenders.
  3. To maximise the effect on road safety, alcohol interlock programmes for drink driving offenders should be compulsory and placed under administrative law. In case major practical or legal issues are foreseen, alcohol interlock programmes should be placed under criminal law.


  1. Countries that want to introduce alcohol interlock programs should, as a minimum, ensure that the interlock devices selected meet the CENELEC standards. Additional performance and data protection specifications are also necessary since the CENELEC specifications are only applicable for the interlock device and the service application, communicating with the alcohol interlock and sending out the event data recordings to a register.
  2. Involvement in the CENELEC working groups is recommended to keep track of the latest technical issues and solutions. For example, issues concerning the connection between the alcohol interlock device and the electronic systems of new vehicles, including electric vehicles.
  3. The role of a service provider depends on the design of the programme and the requirements posed by the national authorities that are responsible for the programme. In many programmes the service provider will be interacting with participants, press, national authorities, and other stakeholders. Therefore, when writing requirements for alcohol interlock programmes, authorities should not only focus on the technical details of the devices, but also on the total package of services that alcohol interlock suppliers can provide.
  4. Many countries have a driver licence administration that is responsible for issuing driver licences and that has experience with the organisation of large-scale administrative procedures. These organisations should therefore be involved in the early stages of discussions on introducing an alcohol interlock programme.


  1. An alcohol interlock programme should not be limited to just the installation of the interlock device itself but rather designed as a coordinated set of activities designed to minimise the possibility that programme participants drive after drinking.
  2. Rehabilitation measures should be tailored to the situation and background of the offender. A medical / psychological assessment before the start of the programme is recommended, as well as continuous monitoring during the programme. The frequency of registered attempts to start the car after drinking serves as an indication that the desired behavioural intentions are not yet present and of the risk of recidivism.
  3. The requirements of the programme should be flexible, e.g. by including a reduction of suspension periods based on the compliance of the participants (e.g. no fail tests during a certain period or continued participation in educational measures). On the other hand, if there are too many fail tests or the driver is caught for driving under the influence while driving in another vehicle, the duration of the programme should be increased.
  4. Removing offenders from the alcohol interlock programme should only be done under severe circumstances, since recidivism rates of the alcohol interlock programme are lower than alternatives such as permanent or temporary driving bans.
  5. Not only the length of the programme, but also the types of rehabilitation measures should be targeted to the needs of individual users. There are a variety of measures that address the underlying causes of drink driving. For an optimal approach we recommend to get health care and behavioural professionals involved, since the alcohol interlock device itself only changes its user’s behaviour while it is installed in the vehicle. A structural change of behaviour can only be achieved with a more comprehensive treatment intervention. Evidence suggests, that psychological and therapeutic approaches with educative elements are the most promising ones (for an overview see: Boets, Meesmann, Klipp et al., 2008).


  1. Strong enforcement is a key requirement of successful alcohol interlock programmes for drink driving offenders. Firstly, the number of participants strongly depends on the number of offenders caught by the police. The participation rate also depends on the level of enforcement and the perceived chance of offenders being checked for alcohol or for their driving licence. If the chance of a driving licence check is low, offenders may be persuaded to choose driving without a driving licence instead of participating in an alcohol interlock programme.
  2. The enforcement of compliance can be done by regularly, e.g. every two months, checking the alcohol interlock device system for fraud and/or attempts of fraud, and simultaneously downloading and analysing the data from the alcohol interlock device’s data recorder.
  3. A clear code on the driving licence for participants of the alcohol interlock programme makes it easier for police officers to detect misuse while checking the driving licence. The harmonised code in Europe is now represented by the number 69, making it easier for police to enforce the requirements across EU borders.


  1. The costs to the offender of participating in an alcohol interlock programme should be kept at a reasonable level so as not to exclude BAC offenders from the lower income groups from participating in the programme.
  2. Decreasing the costs by changing or dropping content from the programme can have a negative influence on the road safety benefits and should therefore be done with care.
  3. In the United States of America and in Australia many alcohol interlock programmes offer discounts for people in financial hardship.
  4. An alcohol interlock programme with good rehabilitation measures will also decrease public health costs and judicial costs generated by participants. Interdisciplinary working groups can provide expert knowledge and experience, and could increase engagement among stakeholders.
  5. It would be beneficial for the participation rates if the additional costs of a rehabilitation measure as part of the alcohol interlock programme are shared by those authorities that benefit from the measures, such as the Ministry of Transport, the Ministry of Justice and the Ministry of Health.


  1. By conducting a pilot prior to the programme and an evaluation during the programme a lot of practical information can be gathered on practical, technical and procedural issues. Shortcomings of the programme regarding content and procedures can be discussed among the stakeholders and improved.
  2. The evaluation period should not only look at short term effects, but also the long term impact. Therefore, we would recommend using an evaluation period of at least five years with at least two evaluation moments, e.g. after 2 and 5 years.


  1. Good communication lines should be established and then maintained between stakeholders from the design phase of the programme onwards.
  2. All stakeholders and participants should get easy access to information on the background, content and procedures of the programme.
Gepubliceerd door
European Transport Safety Council ETSC, Brussels


Dit is een publicatie van SWOV, of waar SWOV een bijdrage aan heeft geleverd.