I think that there might be a difference between murder (cold-blooded) and a righteous execution. Slughorn even said that Dumbledore had banned the subject at Hogwarts. Boy, I'd really be shocked if Dumbledore did that.
He was no doubt aided by none other than Kreacher, the Black house elf. As much as Kreacher hates it, Harry is his owner now and he must obey Harry's every command.
Now THIS is an interesting theory! I hadn't considered Kreacher helping to find the horcruxes.
Maybe that's why JKR wanted Kreacher to be left in OOTP, since he'd likely be important in the final book. He only appeared briefly in HBP, but it was important to establish the fact that Harry is Kreacher's master now.
In OOTP, Kreacher was hiding away what Sirius considered 'trinkets'; one of those might be a Horcrux. In fact, wasn't one a crystal bottle of what looked like blood? Crude, but so was the enchantment put on the entrance to the lake where Dumbledore and Harry found the locket. Don't know if Kreacher stole away with it or not.
Can't wait for the last book.
Did anyone else see Emma Watson on Conan O’Brien’s show last night? She was nervous like any 17-year-old would be but not at all like her character, Hermione. Very bubbly when talking about the movie and Rupert Grint’s ice cream truck.