The regulator must have at least two lawyers on its nine-strong board. Driscoll and Simon Wethered currently fill the two roles.
Wethered was one of five new commissioners appointed in July after a recruitment campaign designed to increase the board’s diversity.
The new recruit will be expected to work between four and six days a month and could therefore earn up to £25,200 a year from the part-time post.
A commission spokesman said £350 was the set daily rate for board members.