In a short article published one hundred years ago, J.W. Headlam presented the thesis that in Athenian law the function of the challenge to torture slaves was to propose an alternative method of trial outside the dikastêrion, a kind of ordeal. The thesis met immediate opposition and despite a brief rejoinder by Headlam to his first critic it has been rejected by those writing on Athenian law up to now, including G. Thür, whose monograph is by far the most important work on the subject. However, the significance of the issue compels us not to let it drop. For it touches not only upon the use of torture, which affects our understanding of the position of slaves, but also upon the Athenian rules of evidence, indeed, their entire method of dispute resolution. The purpose of the present paper is, first (I) to revive Headlam's thesis in a modified form and (II) to answer the criticisms against it. I shall argue that Headlam was essentially correct with regard to the judicial function of the challenge, but his association of it with the trial by ordeal was misplaced. Finally, (III) I shall touch upon the influence of rhetoricians in Athens, for they appear responsible for some of the disagreement.