Staff permissions: Allow Refund to Gift Certicate but NOT Credit Card

In user permissions, you can set whether a staff user can

A) Refund payments 

B) Issue Gift Certificates

When we issue a Refund Gift Certificate the company keeps the client's money, so this requires a lower level of approval - and can easily be reversed. However, when a Credit Card refund is issued, the money is immediately returned to the customer, and thus should have a higher approval requirement. 

I would therefore like to allow my staff to refund payments to Gift Certificates but prevent them from refunding payments to Credit Cards.