Polygraph Evidence in Court: The Legal Position in Germany
Few questions come up as often: does a lie detector result count in court? The short answer is that in German criminal proceedings it is not admissible as formal evidence, while outside the courtroom it is used constantly and to real effect. This article sets out the legal framework and the situations in which a polygraph report actually helps. It is general information, not legal advice — have a lawyer assess your specific case.
Criminal proceedings
In its judgment of 17 December 1998 (1 StR 156/98) the German Federal Court of Justice held that the polygraph is a completely unsuitable means of evidence within the meaning of the Code of Criminal Procedure. A motion to admit such evidence may therefore be rejected — even where the defendant is the one requesting the examination.
The distinction matters. The Federal Constitutional Court had previously made clear that a voluntary examination does not violate human dignity. What is excluded is not the procedure itself but its use as evidence in a criminal trial. An examination without consent would be impermissible in any case: section 136a of the Code of Criminal Procedure prohibits interference with free decision-making.
Civil, employment and family matters
Outside criminal proceedings the picture is less rigid. Civil and family courts apply the principle of free evaluation of evidence and decide case by case whether to take a privately commissioned report into account. In practice such a report is treated as party submission: it is not expert evidence in the procedural sense, but it can support the credibility of an account.
In employment matters an employer may not order a test. It is permissible only at the explicit, voluntary and documented request of the person concerned, and a refusal must carry no consequences.
Where a report genuinely works
The practical value sits before the courtroom door rather than behind it. Typical constellations from our casework:
Clearing an accusation. Someone wrongly suspected wants to show family, employer or business partner that they are willing to be tested. The report works where trust has broken down.
Assessing the strength of a case. Lawyers have a client’s account tested before settling on a strategy: what does not hold up internally will not hold up at the hearing either. We run a dedicated service for this — investigations for law firms.
Settlement negotiations. Where it is one word against another, a test result shifts the balance — factually, if not legally.
Internal company investigations. Theft and fraud cases are often better resolved internally than through a criminal complaint with an uncertain outcome.
What makes a report convincing
If the result is meant to persuade a third party, the examination has to be fully documented: written consent, the complete question protocol, the methodology and scoring system used, the charts themselves and the examiner’s qualifications. Without those elements a report is just a sheet of paper. The procedure is described step by step in our article on how a lie detector test works; the service itself is here: polygraph testing in Hamburg.
The limits of the method
A polygraph tests whether a statement matches what the person remembers, not objective truth. Someone sincerely mistaken responds like someone answering truthfully. And an inconclusive outcome is a legitimate result, not a malfunction. A serious examiner promises neither perfect accuracy nor conclusions on issues that were never agreed in the pre-test interview.
Frequently asked questions
Can a court order me to take a test? No. An examination against the person’s will is excluded in Germany.
Does refusing hurt my position? Legally, no adverse inference may be drawn from a refusal.
May I submit the report myself? You may submit it; how the court weighs it is the court’s decision. Agree the step with your lawyer in advance.
How soon can I be tested? Usually within a few days, and sooner in urgent matters. Our online calculator gives an indicative price in a minute.