If I might stick my oar in again with my own example
I am a decision maker because I make decisions about what action is taken on individual cases. I must make those decisions in accordance with the law and with the organisation's policy, neither of which I determine.

The policy makers for my work do not see individual cases and may not actually have the skills or equipment to make the decisions. If you ring the JobCentre you won't get Iain Duncan Smith making a decision on your benefits.

A call centre supervisor may be a decision maker and may have more discretion and leeway than a normal operator, but they are unlikely to be a policy maker and won't be able to change the rules.
( in vino veritas, Fri 9 Jul 2010, 1:03, Reply)