I think my explanation is wrong but here it is :
There are many tactics followed and for the given situation, Mark uses Legitimating tactics.
It is related to compliance with rules, laws, and regulations.
It is not to motivate people but to follow behind the direction given by the organization
It is least effective for the aspects pertaining to pressure, legitimating
It always speaks about rules and makes the employee to follow
Firing of employees comes under legitimate power.
All these are done to achieve organizational goals.