Every candidate has a resume to submit but I feel that isn't as important as submitting code for review. I always require code from my candidates as I feel it is as important, if not more than a resume. I learn more than just the level of their coding skills but how they think about code and what is important to them. These insights help me understand the candidate better and allows for high quality matching with prospective employers. This contributes to my very high placement rate (over 50%).
Not everyone who knows Perl or programming well is good at code review. It is a different skill that requires having read massive amounts of code over many years. I have been coding for over 35 years, in many languages with the last 15 mostly in Perl. I have reviewed tons of Perl for clients and in various forums on the net. My own code has been very well received (my CPAN id is URI). This deep experience is what allows me to know good Perl code from bad and how to make it better.
The key aspects of code review is knowing which styles, idioms, techniques for a given language are the best ones. Another major aspect of code review is looking for consistancy and seeing that the candidate has a solid vision of how to write code. This isn't necessarily the same as knowing more code but rather putting the proper effort into the code given the coding skills you have. You can always learn more programming techniques in any language but having the correct vision in how to code is harder to learn.
One case in point happened when I had a candidate who had been taking care of his grandmother for 7 years and was out of the job market for that time. His Perl code was in the beginner-intermediate range and showed he needed to learn plenty. But I saw he paid attention to important things such as names, structure and more. His coding attitude was very good even if the actual coding level wasn't. This boded well for his future work. As it happened I placed him in an entry level Perl development job and he has thrived there for over a year and a half.
For more information and recommendations from some candidates I have placed, check out Perl Hunter success page.