On the topic of Dumbledore as head of the Wizengamot: There are a few possible flaws in the arguement that Dumbles could have forced the deatheaters' convictions.
1) He may be 'leader of the Wizengamot' the same way the Speaker of the House is the 'leader of the House of Representatives/Senate' (which ever it is), less overwelming authority and more first among equals/moderator.
2) Several of the supposedly 'Imperio'd' DEs were members of the Wizengamot. The majority of the others may have been reluctant to establish a precedent for prosecuting Wizgamot members in case it may later be used against them.
As for the blood wards, keep in mind, that pre first year, the only wizards who knew/could find The Dursleys' place were members of Team Dumbles. While Wizards/witches occasionally stumbled acrost Harry, it was always while out and about with the Dursleys (and each encounter probably freaked out Vernon and Petunia).
Also I rather suspect many of the reported Potter Sightings were more in the style of Elvis sightings than actually seeing Harry.
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"I've always wanted to be somebody, but I should have been more specific." - George Carlin
1) He may be 'leader of the Wizengamot' the same way the Speaker of the House is the 'leader of the House of Representatives/Senate' (which ever it is), less overwelming authority and more first among equals/moderator.
2) Several of the supposedly 'Imperio'd' DEs were members of the Wizengamot. The majority of the others may have been reluctant to establish a precedent for prosecuting Wizgamot members in case it may later be used against them.
As for the blood wards, keep in mind, that pre first year, the only wizards who knew/could find The Dursleys' place were members of Team Dumbles. While Wizards/witches occasionally stumbled acrost Harry, it was always while out and about with the Dursleys (and each encounter probably freaked out Vernon and Petunia).
Also I rather suspect many of the reported Potter Sightings were more in the style of Elvis sightings than actually seeing Harry.
___________________________
"I've always wanted to be somebody, but I should have been more specific." - George Carlin