First time contributer, so hi to all!

I've been searching and searchign on-line for similar issues and have been unsuccessful.  Seems like everyone has figured out the issue and I just can't seem to figure it out through the Administrative settings. Here is the scenario:

1) A file is check-in and all admin settings prevent certain users from checking out the file unless it is pushed through a change control workflow.

2) However, any use has the ability to right-click the file, and "un-check" the Read-only attribute.

3) Once a user clicks Ok, he/she can then modify the file at will, without any owndership history.

4) HUGE hole.  Please help.