John and Mike work in the same department. Mike is a new employee. John has worked at the company for a long time. John and Mike do the same job. They have the same job title. They have to work together. John likes to do things the way they have always been done. He is very vocal. Because he's been there so long, he thinks he knows how to do things. And he tells others about it, whether or not they ask. Mike tries hard to follow company rules. Mike is a very quiet man. He doesn't talk much. He has conservative and traditional values.

Employees must clock in within 5 minutes of the start of their shifts. They are supposed to clock in at their own buildings, but there isn't any way to check this. John always clocks in at another building so he won't be marked as tardy. He always gets to his work station at least 10 minutes late. At least a couple of times each week, somebody asks Mike where John is. Mike is tired of covering for John. He has kept it in for a long time. Finally, one morning, John is 20 minutes late. Mike has to cover for John 2 times. When John finally appears, Mike tells him he's not going to cover for him anymore. John says, "Hey, I clocked in. I've been doing this for years. As long as you don't say anything, nobody will ever know. Just shut the %&# up and work"

What should Mike do? Explain.