In Act IV of The Crucible, what is the significance of the judges' responses to Proctor's confession?

I think that the fundamental significance of the judges'
revelry at Proctor's "confession" is an affirmation that they won.  Throughout the
trial, there had been the feeling that there was no real and distinct pursuit of
justice.  Rather, it had been an exercise of power.  When Corey refuses to do what the
court says, he is imprisoned because he does not acquiesce.  When Proctor defies the
court, it is taken as a sign of disrespect to the court.  When Francis Nurse presents
the petition of signatures affirming his wife's character, the court wants to
interrogate those 91 individuals.  The court had always set itself up as an instrument
of power as opposed to one committed to the drive for
justice.

When Proctor breaks down and signs the confession,
it is a sign that the court has won.  Someone with the standing of Proctor in the
community has been able to affirm that the court was right.  The judges are elated with
this because it will prove instrumental in demonstrating that their power should be seen
as absolute and vital to the town's interests.  Proctor's confession is representative
of a momentum changing event in how the town perceives the trials.  With Abigail's
departure and embezzlement, Parris' lack of positive reception, Andover's rejection of
their own witchhunts, and good people like Rebecca Nurse and Giles Corey having to
suffer death and humiliation, the judges were looking for something to lend credence and
validation to their endeavors and Proctor's confession gave this to them.  In this,
their excitement and enthusiastic reaction resided.