It seems suspicious that Snape told Voldemort when Harry Potter would be moved from his home. At that point of time, he had Voldemort's complete trust, having killed Dumbledore, why did he need to perform an extra attempt to help Voldemort find Harry Potter?

5 Answers 5


From the Deathly Hallows, page 688:

"You will have to give Voldemort the correct date of Harry's departure from his aunt and uncle's," said Dumbledore. "Not to do so will raise suspicion, when Voldemort believes you so well informed."

  • So, I guess they were planning it prior, and didn't want to change their plans, or didn't know Snape knew... Wow... Commented Feb 10, 2012 at 4:00
  • 3
    @PearsonArtPhoto: That is precisely why I cannot choose the wine in front of me. (Please excuse the mixing of stories.) Commented Jun 12, 2014 at 16:49

Snape does not have Voldemort's unconditional trust. In the books, many people (especially Bellatrix) are shown to resent him and distrust him, pointing to his apparent loyalty to Dumbledore.

The information about Harry leaving from his house is leaked by Snape, but he makes sure that Voldemort does not know about the Polyjuice potion. It's just a part of walking the fine line between winning the enemy's trust and helping his own side.

  • 6
    In fact, I believe Snape's under close scrutiny during the meeting when he does reveal the timing of the move ... and even when he brings it up, his word is doubted. Commented Aug 2, 2011 at 20:11
  • 8
    It's not just Snape... Voldemort doesn't have complete trust in anyone, with the exception of himself.
    – TGnat
    Commented Aug 2, 2011 at 20:48
  • 2
    I'll have to dig it up, but I believe it's part of the memories Harry gets at the end.. Dumbledore's portrait talking about keeping V's trust with limited info, but confunding Dung into suggesting Polyjuice.
    – K-H-W
    Commented Jan 19, 2012 at 2:00

If Snape hadn't told him, despite the fact that Snape MUST have known, Voldemort would have had to assume one of two things:

a) Snape was no longer trusted by the Order - vital information was withheld from him. His usefulness as a spy is ended - if he's untrusted, the Order won't tell him anything important, and may use him for disinformation.


b) Snape cannot be trusted to give Voldemort accurate information. His usefulness as a spy is ended, as Voldemort has no one else in the Order who can serve as independent verification for information Snape gives, and Snape is too good at Occlumancy for his mind to be read.

In either case, Snape's usefulness to big V (and thus, to the Order as a double-agent) ends, likely with his death.

On the other hand, look at the results: moving a vulnerable target during a prepared ambush, the Order suffers very minor losses. Yes, some important characters suffer, but overall the losses are much less than could be expected - the ambush was supposed to leave no survivors. The Order acted heroically and skillfully, and gave as good as they got...because Snape told them the ambush was coming. And, of course, lived to serve them more.

Edit: As Katie's answer shows, this was planned before Dumbledore's death to ensure that Big V trusted Snape - doing so allowed him to continue working against him from within the Death Eaters despite having been cast out of the Order.

  • 12
    :At that point, Snape was not part of the order. Also, he did not tell them about the ambush, all precautions were merely anticipatory (at least in the books)
    – apoorv020
    Commented Aug 2, 2011 at 19:45
  • Perhaps not in the Order per se, but 'trusted by Dumbledore'. That still makes him invaluable.
    – Jeff
    Commented Aug 2, 2011 at 19:50
  • 9
    This is the 7th book we are talking about. Dumbledore dies in the sixth, and Snape is publicly proclaimed his murderer.
    – apoorv020
    Commented Aug 2, 2011 at 19:56
  • 2
    The order planned it. Better to know its coming at you than wonder and be caught unawares.
    – Chad
    Commented Aug 3, 2011 at 16:34
  • 1
    The ambush traded Harry for Mad Eye. Not quite sure how good that trade is if you see it objectively, since one is a fledgling teenager and the other is an experienced Auror. He is the boy who lived, but at that point in the sorry the title was more of a prophecy rather than actual proven ability.
    – Lie Ryan
    Commented Jul 6, 2014 at 2:57

I just wanted to add to the first comment here, with regard to Dumbledore telling Snape to tell Voldemort. Yes, in order to gain the unconditional trust of Voldemort.

Dumbledore's reasoning was that he wanted Snape to become Headmaster, and protect the school from the Carrows.


Or just accept the obvious answer: It's a plot hole. Voldemort already knew that Snape was not trusted by the Order from the point where he killed Dumbledore at the end of the previous school year. Even if the plan to move Harry had been agreed upon before that, there was no way for Voldemort to have known that. There is, therefore, no logical reason why Snape could not have said that he didn't know.

  • 3
    You're probably being downvoted because we rather dislike "plot hole" answers. In this case in particular, the answer, which is not a plot hole, is specifically stated in the book, see the accepted answer.
    – Kevin
    Commented Apr 14, 2012 at 2:38

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.