When did the "trace" come about?

[weasleys.rock]

No: HPFGUIDX 176189

weasleys.rock:
It is in my opinion that the entire wizarding community is being
traced or "watched." Magic is said to put out energy which could be
tracable by some means which I think the MOM has tapped into. The
trace in heavily put upon underaged wizards and witches because they
are, if you will pardon the term, irresponsible. It's just like
driving. We cannot learn to drive until the law thinks we are
responsible enough to drive a motor vehicle. The same goes with magic.

zanooda2:
> Ah well,
> if JKR was ever asked about it, she'd probably say that the Trace
> was not yet invented when LV was underage ... :-).

weasleys.rock:
This goes along with my theory that the whole community is
being "watched." There may have been a flag to say that magic was
performed in front, and towards, muggles, but not by WHOM.

Random832:
> The fact that it traces magic _around_ Harry rather than just
> specifically what is cast BY Harry is why none of the adults
> rescuing him can cast spells either.
> NO-ONE can do magic around Harry wherever he is until the Trace is
gone,
> or his location will be revealed. If he weren't being targeted, I'm
sure
> it'd be just fine because the ministry would just assume "oh,
there's
> adult wizards around" - the problem is that the trace would still
be
> triggered in the first place, revealing the location.

weasleys.rock:
I agree here with Random832. If underaged magic was not traced at the
time LV committed the murders then the wizarding world would have
most likely been discovered already. That was only 50 or so years
earlier. The most likely reason why Morfin was accused of the murders
is because it breeches the Code of Secrecy which was put into place
sometime in the 1600s, according to the HP Lexicon. The same for
Pettigrew's murders of the 12 muggles. Not because it was underaged
magic. This supports my claim that MOM is watching ALL magic being
used.

The children are not banned from doing magic. I agree that it is up
to the adult wizards and witches to moderate the children's use of
magic. I believe that in a magical household, the restriction is a
bit lenient, unless, of course, there are muggles around. It seems
that only when muggles are present, is the decree absolutely
necessary. Case in part, the Weasleys always practice Quidditch
during the summer in a field where muggles can't see, yet they never
seem to get a notice from MOM. Harry, unfortunately, is always
surrounded by muggles when he is not at school. I believe that even
if he was in a room alone but muggles were nearby, say in another
room, he will still be notified by MOM if he preformed any magic,
especially if he were still underaged.