The lecture shows, by means of an example the importance, cooperation in regard to the determination of facts has. It makes clear that all parties involved, judicial authorities and investigation authorities, need to work together form the very beginning. At the same time it clarifies at which point cooperation ends and the authorities investigate further depending on their respective assignment of tasks. Conclusion: only, if both authorities have the same level of information regarding the determined facts, a more in-depth investigation by the accident investigation authority and determination of causes without blaming someone is possible without interference by the judicial authority or legal representatives.