The Salem witch hunt has entered our vocabulary as the very essence of injustice. Judge Samuel Sewall presided at these trials, passing harsh judgment on the condemned. But five years later, he publicly recanted his guilty verdicts and begged for forgiveness. This extraordinary act was a turning point not only for Sewall but also for America's nascent values and mores. In Judge Sewall's Apology, Richard Francis draws on the judge's own diaries,...