I just realized my employee agreement (which I signed several years ago) has a clause that prohibits me from being a referee for another employee at the firm. The clause does not distinguish between personal references and work-related ones. The effect of the clause is such, that it does not allow people in supervisory or team-leader roles to act as referees for their subordinates; it doesn't say if current employees can be references for former employees.
The employer recently reminded another employee (not me) that it was their policy that only they are not allowed to act as referees or issue written references for former employees. This seems utterly unreasonable to me, and I was tempted to bring up how unreasonable I thought it was. However, I'm baffled as to why any employer would want to stipulate this in an employee agreement.
Is there a perspective to this I'm missing? What is the motivation for it?