this question is for Uk law, I want a detailed answer using uk criminal law to find whether or not they are liable

Question one is a non-compulsory seen question. 1. Josie and Jim were in debt to Louis. Louis was known to have a bad temper. Josie and Jim realised they may come to harm if they did not pay off their debt. One evening, Josie, who was at home alone, heard someone banging on their front door, shouting, "Open up, I know you are in there. I want my money." Josie spotted Louis carrying what looked like a crowbar in his hand. Josie panicked and jumped out of her first-floor window. She fell to the ground landing on her head and died instantly. The following evening Louis returned to their house and set fire to newspapers under a wheelie bin in their front garden. A fire started and spread rapidly onto the house. Unfortunately, their uncle, Arthur, who had been staying at the house died from smoke inhalation. Jim was out at the time being consoled by friends over Josie's death. Louis claims that he only wanted to frighten Josie and Jim into settling their debt. Advise Louis on his liability, if any, for homicide