The continuity editors of the Potter books surely earned their wages – other than things like math and dates, there are remarkably few lexicon.org/search-wpsolr/?wpsolr_q=inconsistencieswpsolr_fq%5B0%5D=tags:inconsistencies">inconsistencies in the Potter series.  But there is a small one in Order of the Phoenix that proved to be a lot of trouble for Jo. In the original Order of the Phoenix, when Draco begins abusing his power as a member of the lexicon.org/thing/inquisitorial-squad-2/">Inquisitorial Squad, lexicon.org/character/ernie-macmillan/">Ernie Macmillan declares “It’s only teachers who can dock points from houses!”  It didn’t take long for eagle-eyed fans to notice that lexicon.org/character/weasley-family/percy-weasley/">Percy Weasley did in fact dock points from Ron in Chamber of Secrets, so this was a contradiction. Unfortunately, when Jo tried to address this on lexicon.org/source/guide-to-rowling-website/">her website, she only dug herself a deeper hole.  She said, “Ron got it wrong in ‘Phoenix’, from which we deduce that he hasn’t been a very authoritarian prefect thus far; he clearly hasn’t been taking points from anybody.” Except it wasn’t Ron who made the claim, it was Ernie Mac – who, we can all agree, is the type of lexicon.org/thing/hogwarts-prefects/">prefect who would know the system backwards and forwards. Fans spent considerable energy coming up with better explanations.  Maybe only prefects in sixth year and above could take points?  Maybe prefects could only take points from underclassmen?  Maybe prefects could only take points from their own House? In the end, Jo chose to lexicon.org/edits-changes-text-op/">change the offending passage in the next edition of Order of the Phoenix: Ernie now says, “You can’t take points from fellow prefects, Malfoy.”  That is at least consistent with Percy’s actions, though it still seems a system ripe for abuse – with Draco as a prefect, how does Gryffindor have any House points left? In general, Jo seems to not have thought through the prefect system as diligently as she did most things.  Another potential issue was circumvented when Order of the Phoenix revealed that lexicon.org/character/potter-family/james-potter/">James Potter had never been a prefect, but Sorcerer’s Stone said that he had been lexicon.org/thing/head-boy/">Head Boy.  It seemed like the former should be a prerequisite to the latter.  But in Half-Blood Prince, Harry is made Quidditch captain, and Hermione says that it affords him the same privileges as prefects (namely, use of the lexicon.org/place/hogwarts-school-of-witchcraft-and-wizardry/hogwarts-fifth-floor/prefects-bathroom/">prefects bathroom).  So the assumption is that James became Head Boy by way of Quidditch captaincy. And an inconsistency that remains in the books is the form of the prefect pins – shiny silver in Sorcerer’s Stone, House colors in Order of the Phoenix.  Let’s just assume there was a redesign of the badges in the early ‘90s to reflect more House pride, and leave it at that.