Is Boris Johnson a Dead Man Walking?

The word gates has become a suffix which we ad to say that there's a scandal about something. So nowadays you could say, for example, a football manager whose team has been losing over and over again, one more game or one more defeats and they will be pies - that manager is a dead man walking. And it's from prison language. Originally, a person waiting to be exec cuted, to be killed for the crime they committed, was said to be a dead manwalking, not literally.