When investigating an offence, it is important that all material which is of importance to the investigation should be disclosed. Otherwise, the police and the prosecutor will not be able to gain a clear impression of what has happened, which could result in the suspect not being tried for the offence.
The police and prosecutor must therefore question everyone who has information to give. This is the case, for example, if you have seen a crime being committed or if you have found out something that has a bearing on the crime. Even if you do not know anything or have not seen anything, it could be important to tell the police and the prosecutor this very fact.
In Sweden we have something that is known as a general obligation to testify. This means that you are obliged to witness in court if the prosecutor or the suspect and his/her defence counsel consider it necessary. In other words, it is not possible to decide yourself whether or not to be a witness. Exceptions are only made, for example, if you are a close relative of the accused.
If you feel worried or uncertain, you are always entitled to receive help and support. In many courts there is a system of witness support and special waiting rooms for witnesses. Contact the district court before the hearing if you have any questions about the way things operate in that particular court.