Driving in Germany: Duty to act
Much like requirements of Good Samaritan laws in the United States, drivers in Germany have a responsibility to render aid.
According to German law, there's a duty to help in case of an "accident or common danger or emergency" if help is necessary and appropriate, and the helper is not significantly endangering him/herself or violating other important duties. Violating this duty to help constitutes a criminal offense.
On the civil side, there's no specific law shielding helpers from claims for mistakes they make while helping. However, the law applied in these situations essentially limits the liability to grossly negligent (and, of course, intentional) mistakes in case of non-professional helpers. The liability of professional helpers is not limited. In simple terms, if persons provide help in an emergency situation as best as possible within the limits of their capabilities, they are generally not subject to any liability. Additionally, emergency helpers are covered by the German public accident insurance if they injure themselves in the course of helping.