Is Additional Evidence Besides Conscious Parallelism Required to Prove Conspiracy Cases ?
In McClure v. Owens Coming Fiberglas Corp., 188 Ill. 2d 102, 134, 720 N.E.2d 242, 258, 241 Ill. Dec. 787 (1999), the civil tort conspiracy case extensively cited by the trial court, our supreme court followed federal antitrust cases, as well as tort conspiracy cases from other jurisdictions, in holding that conscious parallel conduct alone is insufficient proof of the agreement element of the tort of conspiracy. McClure, 188 Ill. 2d at 142, 720 N.E.2d at 262.
The court noted that federal courts require additional evidence besides conscious parallelism before an agreement violating the Sherman Act can be inferred in order to, avoid the inadvertent condemnation of nonconspiratorial conduct. McClure, 188 Ill. 2d at 136, 720 N.E.2d at 259, citing Coleman v. Cannon Oil Co., 849 F. Supp. 1458, 1466 (M.D. Ala. 1993).
"The requirement is intended to help assure that there is a reasonable basis to conclude that persons exchanged assurances of common action or otherwise adopted a common plan, albeit not necessarily through meetings, conversations, or exchanged documents." McClure, 188 Ill. 2d at 136, 720 N.E.2d at 259, quoting Coleman, 849 F. Supp. at 1468.
Such additional evidence can include evidence of:
(1) actions contrary to the defendants' economic interests,
(2) a motivation to enter into such an agreement.'" McClure, 188 Ill. 2d at 136, 720 N.E.2d at 259, quoting Petruai's IGA Supermarkets, Inc., 998 F.2d at 1242.
Given the ambiguous nature of the evidence in a parallelism case, the court found support for its holding in the clear and convincing standard of proof applicable to conspiracy cases to be proven by circumstantial evidence, noting that under that standard, if the evidence relied upon is as consistent with guilt as with innocence, the court must find that the conspiracy has not been proved. McClure, 188 Ill. 2d at 140-41.