Whenever I've been hanged, which has been many times in my life, my
lips were a darkish red colour, and to my knowledge, my mouth has
never been open. Too, although you never asked, my face has been
described as quite pale when I've been hanged and was unconscious.
But, whenever I've allowed myself to be garroted, which also has been
many times, my face goes dark until I'm unconscious, and if the
strangulation is continued, my face goes pale after a minute.
However, I have seen the faces of other hanged people, two males who
were into extreme auto-erotic asphyxia (as I am), and three other
people (two women and one man) who's hangings were suicide. The two
men who were into auto-erotic asphyxia were my older brother and my
first husband. The two women were my older sisters and the man who
commited suicide was my second husband. In the cases of the three
suicides, their faces were all pale and their lips were still red
colour and not much darker than normal. As for the two males who were
into auto-erotic asphyxia, when they hanged and were cut down in time,
their faces were a little on the dark side, and their lips were a much
darker shade of red. However, when their hangings lead to their
deaths, their faces were pale and their lips weren't much darker than
normal. There is one common factor though with regard to all five of
their final face and lip colour. All five people suffered fatal total
neck separations. Maybe that had something to do with the changes in
colour, I don't know.