Mark lived in a semi-detached house with his beloved cat, Atticus. Brian, a widower, lived next door in the other half of the building. Mark and Brian had been friends for many years, until one day Atticus killed Brian's favourite canary. When Atticus killed Brian's canary, Brian screamed out to Mark over their shared garden fence, 'I will get that cat, and you will be sorry that you didn't keep it under control!' On hearing this, Mark felt very worried about what Brian would do, as he sounded extremely angry. From that point on, Brian and Mark's relationship deteriorated, and they did not speak to one another. Mark discovered nails on his driveway (having driven over one that punctured his car tyre) and animal faeces on his front doorstep. Mark also received daily phone calls where the caller hung up as soon as Mark answered. Mark believed that Brian was responsible for all the strange events, but he did not know for sure. After several months of the same events, Mark became scared to go out and was diagnosed with severe depression as a result. One evening, the phone rang, and Mark answered it. Mark recognised that it was Brian calling when Brian said to Mark, 'have you had enough yet?' and then hung up. Mark felt a pang of anger as he now knew for certain that it was Brian who had been making his life hell for so long. In response to the call, he stormed out of his house and knocked on Brian's front door. When Brian answered the door, Mark pushed him with some force. As a result, Brian stumbled backward, hitting his head on the corner of the hall table, causing a small cut. Shocked at his own behaviour, Mark ran back to his home and called 999 to request an ambulance for Brian. He explained that he had hurt someone but that he did not think it was life-threatening. Brian was a hemophiliac, and when the paramedics arrived an hour later, he had bled to death. Please see below:

Consider only Mark's liability for any fatal and any non-fatal offences to the person.