The Rules Committee of the Illinois Supreme Court is considering some changes to the Illinois rules governing class actions. One of the proposals is the truly awful idea of mandating that discovery on the merits be postponed until the court has ruled on class certification.
Why would this be so awful, since discovery about class-certification issues would still be allowed? Answer: Because most discovery pertinent to class certification is also relevant to the merits of the case, and the proposed rule would engender motions galore, as the parties seek court intervention to define what is and isn't discovery "on the merits." (An unintended effect of the proposed rule is that the courts may end up ruling sooner on class certification--precisely the result that the tort-reform advocates don't want.)
For more on this problem, see this past post.