This article provides an ethical critique of the Good Clinical Practice (GCP) and Declaration of Helsinki (DoH) documents. While the previous criticisms of GCP are entirely correct, there is much more wrong with the document than has previously been acknowledged, including a circular definition and an astonishing vagueness about ethical principles. In addition to its failure to provide adequate ethical protection of participants, the procedurally dense nature of GCP lends itself to a box-ticking culture where important ethical issues are overlooked because they are not ‘mentioned on the form’. In contrast, the DoH is a much more effective ethical document, but actually goes too far in one respect. It transpires that the best ethical guidelines for clinical research would be neither over-prescriptive in regard to particular ethical issues (as the DoH is) nor neglectful of them (as GCP is); correctly framed ethical principles will provide sufficient protection to participants while also ensuring a culture of ethicovigilance in clinical trials.