I wouldn't employ any coder nowadays without some form of test and evaluation. I've evaluated a few people over the years both for my own company and as a consultant for others. Reputation or status from end customers or references shouldn't count for as much as you'd think - customers or colleagues might be happy with the functionality / presentation of work they have received, but they would be unaware if the code is a disaster behind the scenes, because they don't have the expertise to know better.
I've found a monitored and fairly open ended test scenario useful, not only because it allows multiple approaches, but it's also indicative to see how candidates access information online if they find it necessary, where they look and whether they can tell good from bad resources.
As Ralph points out, for remote candidates they can easily get assistance, so I'd arrange a set start time and duration to receive and complete the test, and would google the test scenario before to see that it's not got a ready solution, and any code received to check whether they've just copy/pasted stuff.