Availing Compensatory Leave ..

Sir,
one of my collegue he is a staff car driver he wants to avail compensatory leave..but in the office they are insisting to take overtime allowance..
can he take compensatory leave by not taking cash

Compensatory off is the most unstructured leave benefit. Its never clearly documented and always attached with the clause "discretion of reporting manager" which you can read as "by the mercy of your manager".
Kindly check if the driver is on organisation payroll and compensatory benefits are applicable to him. My guess is that he has rights to claim leaves and refuse the cash benefit.