If I accidentally find out that someone else committed a crime, and I don't sue him, will I be punished if it later turns out that I knew in some way? In the above example, what happens if it is not ‘me’ but a lawyer? And is it possible for a lawyer to sue him?
1 Answer
This depends on where it happened, and also on what you knew when.
Usually, to "sue somebody" describes initiating a civil lawsuit, while "reporting someone to the police" or words like that describe making the authorities initiate a criminal investigation. There may be some cases where one is required to start a civil lawsuit, but they are not likely to matter here.
There may be requirements to report a crime, or at least some crimes, to the authorities, but the details differ from country to country. A witness under oath may be required to answer fully and truthfully, but that is different from volunteering information.
In germany, there is §138 StGB enumerating those crimes where it is a crime not to report them if one knew about them in advance.