Fuzzy-trace theory (FTT) provides well-researched scientific principles that explain worrisome forms of false memory in the law. False memories are of great legal concern because memory reports are frequently the evidence that determines guilt/innocence and are sometimes the only evidence that crimes have been committed. FTT’s principles reveal errors in commonsense theories that jurors use to judge the credibility of witnesses’ memory reports. This science versus commonsense disconnect is salient in cases involving child witnesses, eyewitness identifications, and confessions. The consequences of this disconnect for justice could be ameliorated by a simple change in federal rules of evidence.