One of the most well-known critics of Intelligent Design has been Brown University biologist and theistic evolutionist Ken Miller. In the words of Anika Smith:
For as long as Darwinian biologist and Brown University professor Kenneth R. Miller has attacked intelligent design (ID), design proponents have refuted him. While there are occasions where Miller has wisely dropped his refuted objections, more often he will keep trotting out the same stale arguments. His tendency to hold onto his misconceptions means design theorists have to continually point out how he misrepresents their arguments. Several of these responses to Miller are worth revisiting, and because we've recently had some new rebuttals to Miller, we've now put together a list of links to some of the best.
Those interested in reading some of these rebuttals can find the links to them here.
RLC