How do you test a piece of software or module that came for retesting, meaning you found some bugs, submitted them to developers that fixed them and sent the module back for retesting?
I think that, whether roles such as QA experts are more or less defined in the team, the person who found the bugs should accurately check the software, as she's the one with more experience on the history of the bugs. It would also be useful to hand the software to another tester, which could look at it with a different perspective and identify more and/or better tests.
The important thing is that tests should be repeatable, better yet automated where possible, otherwise it would be very difficult to positively assert that the bug has been fixed.
6 hours ago