Really the dog should be taken away for its safety....I've seen the leash across the trail result in a crash. Dog owner then tried to attack biker for hurting her dog. Stupid entitled twat. Felt bad for the dog.
At 20kph the closing speed is roughly 18 feet per second. By the time the owner reacts and the dog reacts... how many seconds. That assumes the bike is going the speed limit AND sees the leash and gives good warning before it is too late.... An e-bike at 35 kph is roughly 32 fps, but that is another thread! If they don't care about the safety of their dog, don't have a dog!