Wilk vs. AMA
Wilk vs. AMA was a US Federal Court case (895 F.2d 352) in which a chiropractor Chester A. Wilk and 4 chiropractor-colleagues sued the American Medical Association for boycotting the practice of chiropractic "medicine".
In 1976 the 5 chiropractors filed an anti-trust lawsuit because they claimed that the AMA illegally boycotted the practice of chiropractic medicine. The reasoning behind the boycott was that the field of chiropractic "medicine" is both faith-based (or pseudo-scientific) and that chiropractors generally do more harm than good with health care.
The end result
In 1987 the Federal judge Susan Getzendanner ruled in favor of chiropractors. The judge made it clear that she was not ruling either for or against the efficacy of chiropractic treatment, since the trial evidence was primarily anecdotal. The ruling was that the AMA unfairly competed against chiropractors because it prevented its members from recommending chiropractic services. The ruling was upheld by a Federal appeals court. It was appealed to the US Supreme Court 3 times; each time the Supreme Court refused to hear the appeal.
If the AMA had presented better scientific evidence that chiropractors harmed patients, they might have had a favorable outcome from the trial. As the judge observed the evidence, the AMA seemed to be more interested in financial aspects rather than patient well-being. Since the time of the trial, some peer-reviewed scientific publications have become available that do show potential dangers (e.g. stroke) from chiropractic treatments (see the main article on chiropractic).