From seeing a lot of shows and movies, it seemed like murder just happened. People would see someone on the road, kill them and move on. Or someone would get insulted at a bar or restaurant and someone would pull out a sword or dagger and kill that person. Was that really how things worked? It didn’t seem like there were any real policing and since villages and towns seemed so rural, maybe it was much more challenging to enforce laws?
This is obviously a very broad question but you might enjoy this answer by /u/Steelcan909 for some insight into part of the question in the 11th century in London, England - mostly on the specific issues of how murderers were caught and what a murder trial would look like. https://www.reddit.com/r/AskHistorians/comments/hu4lnj/im_an_average_guy_living_in_london_in_1097_one/