Dylan was originally designed by committee back in the days when it was designed by people @ Apple, Harlequin and CMU.

And many of the people involved with that were also involved with the Common Lisp standardization (like David Moon, Scott Fahlman, etc).

Common Lisp is a pretty interesting example, but due to the politics of the various companies involved, the vast amounts of code in each of the various Lisps, and so on, I don't think it is a fair reflection on "designed by committee". It is just what that committee was able to design given the constraints imposed upon them.

In many ways, Dylan was a stripped down and much more minimal Common Lisp, but with aspects of Scheme as well. But Dylan was designed from a green field, while Common Lisp was designed with a number of existing Lisps in mind that each had a stake.