Danny is a time served motor mechanic and he has been working at Campbell’s garage for the last five years. On Friday morning, Mrs McGregor, who was having trouble with her car brakes, brought the vehicle into the garage to Danny to see if he could fix the problem. Danny finally got round to looking at the car at about 3 pm that day and he carried out a couple of basic tests to see if he could pinpoint the problem. After working on the brakes for about 45 minutes, Danny tightened some screws and the problem appeared to have been sorted. At around 4 pm, Danny remembered that he was to meet his girlfriend, Karen, for a few drinks and he rushed away from the garage to head down to the pub at the bottom of the road. The next morning, Mrs McGregor came in to collect her car. Later that day, Mrs McGregor was seriously injured in a car crash. Apparently, her brakes failed when she approached the busy Blackwater junction and she was hit by an oncoming car. Danny feels dreadful about this — perhaps he should have spent more time working on Mrs McGregor’s car. After listening to Danny’s worries, Tom, the garage owner, has reassured him that he did everything that could be expected of a reasonably competent mechanic.