This might just be my mind blurring fanfiction and canon, bit I've read a few stories where someone makes multiple rapid apparition jumps in various locations to lose someone following them. I can't remember if this has any basis in canon, but is something like this possible? Does apparition leave a signature or something that can be followed?

 

No, apparition is supposed to be untraceable unless you literally "hitch a ride" - see DH.

However, this comes with two caveats:

1. If you disapparate or apparate around magical children then their Trace will pick it up.

2. It seems likely that the Ministry has other means of tracking magic in specific locations. Certainly the Fantastic Beasts script, if you consider that canon, indicates that MACUSA has a way of tracking magic in New York.

These two come with their own caveats, though:

1A. It does not appear that the Ministry routinely uses Trace information for general monitoring or crime purposes. It is used solely for underage magic notices.

2A. From Fantastic Beasts this monitoring appears to detect the location of heavy magical activity but it does not distinguish users or type of magic being used.

 

What do you make of movie scenes in terms of canon? I remember Harry and Hermione making several apparition jumps to avoid snatchers in DH.

 

I don't recall that specific scene, but in any case I would never consider the original movies canon since they directly contradict the books in many places (and weren't written by JKR). With respect to Fantastic Beasts I consider the script canon as it was written by JKR and does not contradict the books, but I do not consider the movie itself (e.g. its props, special effects, etc) canon.

 

From book 7:

“But how did they find you so quickly? It’s impossible to track anyone who Apparates, unless you grab hold of them as they disappear.”

 

Who said it? I assume it was one of the trio, Ron ?
Since it is one of the trio, it is their own opinion not a rule, they might lack information on methods of tracking apperation.
Which brings us to divination, just not the useless type which allow an author to do wonders

 

Lupin said it.

 

I'm working toward a theory that the Trace doesn't ping when there's an authority present- whether a professor, a Ministry official, or an Auror. The Trace may activate, but the notice back at the Ministry also marks that an official was nearby, meaning it isn't counted as a violation. This explains Harry escaping prosecution for everything done near Dumbledore, at the Quidditch World Cup, in Diagon Alley over summer... even portions of the graveyard confrontation, since Macnair was present.

Harry may have been 'pinged' for the AK Peter used on Cedric, but then the Trace might have also noted other nearby magical entities included two dead guys named Peter Pettigrew and Tom Riddle, and that notice would be quashed before it was sent out of Hopkirk's office.

 

I think you have to distinguish between the Ministry receiving the Trace information and the act being contrary to the Decree for the Reasonable Restriction of Underage Sorcery. You only receive an owl if your act of underage magic was contrary to the decree.

So that means all magic cast in term time does not receive a notice, because the decree only covers magic cast during school holidays. It also means that pre-Hogwarts magic is not enforced against, since as far as we know it only applies to magic cast from the summer after first year and beyond. And it means that duplicate offences are not enforced: in OotP, the Ministry only sends a single notice even though Harry cast two spells (Patronus and Lumos).

In practical terms this basically means that Mafalda Hopkirk is on holiday whenever school is in session XD

 

As the HP wikia says:

Given the existence of the Misuse of Muggle Artefacts Office, the Office for the Removal of Curses, Jinxes, and Hexes and the Office for the Detection and Confiscation of Counterfeit Defensive Spells and Protective Objects, all of which in the strictest sense can be said to be tasked with dealing with 'improper' use of magic, it is possible that the the Improper Use of Magic Office is actually a sub-department divided into subsections for different kinds of 'improper use' of magic, all of which receives their assignments from the figurative 'command centre' that is the Improper Use of Magic Office, which receives intelligence about misuse of magic and delegates the practical and regulatory aspects of the job to the relevant subsection while the Improper Use of Magic itself attends to the judicial part, as well as maintain written correspondence with the involved parties, as well as notifying the Department for Magical Accidents and Catastrophes if required.

 

While Lupin is an educated man, he is not omniscient.
He might not be aware of methods of doing so, which leaves interpretation in the hands of the authors

 

I think the Trace is more like area control than many people realise. From the fact that underage Tom Riddle got away with framing Morfin Gaunt for the murder of the Riddle family, it seems to me that not only can the Ministry not tell who has cast the magic they detect, but further they can't even tell whose Trace it was that recorded the magic. Basically they have area control over any area in the vicinity of an underage wizard, wherever that happens to be. Within that area they can tell if magic has been cast and what magic it was, but not who cast it or which underage wizard was present to detect it.

This further cements the "only Muggleborns get notices" point, because it means basically they have to give out notices on the basis of an assumption: if magic occurs in an area known to contain an underage Muggleborn and no other wizards, you assume it came from the underage Muggleborn.

Two more examples of adult magic at Harry's house during the summer are Mr Weasley in GoF and Tonks in OotP. Speculatively the fact that they are both Ministry personnel may be relevant to the lack of notice given.

 

Sesc: Then it would appear I owe you some sort of apology. You see, I write for the wiki and occasionally adds my own theories to the "Behind the scenes" section if a) they seem objectively plausible or b) are shared by others. That run-on sentence were of my doing. I am sorry that my English isn't as good as you might have liked it to be, but alas, it's an unfortunate consequence of it being only my second language as well as reading too much George R. R. Martin.

That being said, in all fairness, while canon not saying something didn't happen isn't the same as saying it did,, it is a very real difference between contradicting something and saying that something hasn't been stated to be the case, but very well could have. And I firmly believe that, while the wikia might be flawed, on the subject as to whether or not the "run-in" sentence in question contradicts canon or not, I am in the right, and you are in the wrong. And since you were the one claiming that to be the case, the burden of evidence lies with you. We are getting a bit off topic, but if you are willing to discuss it further and prove to me that the sentence is contradicting canon, please do. I am completely open to your views, granted it is in in a new thread in which our debate can take place.

 

Are we really at the point where we're making up excuses as to why something in canon isn't canon, just because we want it to be something different?

 

I'm just saying it isn't shut case like Gamp transfiguration law.
Lupin while educated, he isn't the top authority when it comes to magic, we only have his opinion.
So I keep open mind.

@Secs Lupin isn't charm master or divination master (if we assume Divination is more than just what is shown in canon), it could be he isn't aware of some obscure methods that require certain amount of skills and training.
I don't say the method need to be easy or well known, it is just clearly not publicly known.

 

Actually, there is, Sorrows: the reason why Harry wasn't convicted in OotP. They have a right to use magic to defend themselves if they need it. Muggleborns are even more concerned by that, since they don't have parents/family to do it for them.

Of course, the real reason it doesn't happen is probably because Purebloods wanted to keep teaching their children during the holidays, but you don't want your students unable to protect themselves in case.

 

That sounds like crazy muggle talk.

No one shall separate a wizard or a witch from their wand!