Which abstinence proof does the MPU require for cannabis?

Whether an abstinence proof is required for a medical-psychological assessment (MPU) after cannabis use depends on the individual case. The driving licence authority (Fahrerlaubnisbehörde) sets out in its order which questions the assessment should answer (§ 11 para. 6 FeV, Driving Licence Ordinance). Under Annex 4 FeV, item 9.2.2, fitness to drive is restored after cannabis misuse has ended “if the change in cannabis use behaviour has become stable”. After dependence (item 9.2.4), the annex generally requires “one year of abstinence”. The assessment centre (Begutachtungsstelle) will tell you which type of sample and which period it requires.

What exactly is an abstinence proof?

An abstinence proof is a report from a laboratory. The laboratory examines a sample for breakdown products of THC, the active substance in cannabis. The report states whether these substances were found or not. A single sample is a snapshot. A series of samples gives a series of such snapshots.

One negative test says little about a longer period on its own. For this reason, assessment centres often work with several samples over a set period. Depending on the programme, samples may also be requested at short notice. This is one of the points you should clarify in advance.

Urine test: what it shows and what it does not

The urine test is the best-known method. It shows that cannabis was used most recently. It does not show how much or how often someone used. With frequent use, the substances can stay in urine longer than with occasional use. The exact period depends on several factors, including metabolism and how often the substance was used.

Online, you will often find time frames in tables published by providers. This article does not cite an official source for them, so no days or weeks are given here. Do not rely on a figure from advertising. Ask the assessment centre which period it requires in your case.

Hair sample: a look further back

Hair analysis reaches further back than the urine test. A specialist service takes a hair sample from the head, usually a strand close to the scalp. In the laboratory, the hair is tested for cannabis substances that are stored as the hair grows. You can find more about this procedure in the article How far back does a hair sample show cannabis use?.

Hair length matters. Many assessment centres require a minimum length so that the required period is covered. The required length differs between providers. If your hair is short, ask early whether another type of sample is an option.

How to organise the proof properly

The assessment centre usually tells you which proofs it needs, over which period and at which facility. Ask for this in writing. Before you pay for a sample, check whether the laboratory and the collection point are accepted by the assessment centre. A proof that the centre does not recognise will not help you.

• Ask which type of sample is required and over which period.
• Confirm which laboratory and which collection point are approved.
• Enter all appointments and deadlines in your calendar.
• Keep every original laboratory report and submit copies.

An example of how planning can look

Imagine the assessment centre requires urine samples over several months, and the appointments are unannounced. Someone who only tests on a single day does not know whether they have covered the period reliably. Anyone going through such a programme is best advised to start a list from the outset with date, type of sample and laboratory report. This saves a lot of time if questions come up.

Why a clean test alone often is not enough

The abstinence proof is one part of the assessment, not the whole assessment. The centre also wants to know how you have dealt with your cannabis use and what you have changed since. A negative test without a discussion of your own use often seems incomplete.

Before the assessment, it is worth clarifying which questions to expect. Counselling can help you organise your thoughts. Our article on preparing for the MPU shows what you can pay attention to.

Prevention: an honest look at your own use

An honest look at your own consumption is part of the preparation. If you notice that it is hard to stop on your own, seek help early from an addiction counselling service. There you can talk openly about your use.

What a laboratory report should contain

A laboratory report should state at least the sample number, the collection date, the laboratory, the method and the result. Ask the assessment centre whether it requires further details. Check the report as soon as you receive it for names, dates and sample number, and report any errors to the laboratory before you submit it.

What to do after a positive result

A positive result during a programme is serious. Call the assessment centre as soon as possible, ideally on the same day, and ask how to proceed. Legal advice before any written statement is sensible.

What you can do now

Put the documents from your assessment centre and the decision of the driving licence authority side by side. Check which proof is required and by when it must be submitted. If you are unclear about the periods or the validity of a sample, a lawyer specialising in traffic law can help. We cannot provide legal advice here.

You will find further articles on driving licences, checks and limit values in the section Road traffic. The article What does the THC limit of 3.5 ng/ml mean? explains the connection with the limit value.