Parris can be described as a flat character. He does not undergo any significant change in his character and the qualities he presents. For Parris, the truth of the accusations of witchcraft in Salem is not an issue. Unlike Hale, Parris never doubts the virtue of his actions. He only begins to doubt the effects of his actions and to wonder about the consequences of his role in the trials as they might impact his personal safety and position.
The changes for Parris consist largely in his sense of security.
As challenges to the validity (both moral and legal) are brought against witch trials in communities surrounding Salem, Parris worries that the court in Salem may be subject to the same challenges.
Parris fears that the hanging of two such upstanding citizens as Rebecca Nurse and John Proctor the next morning will incite a rebellion in Salem similar to the one in Andover
He also worries about physical harm being done to him as a result of his role in the trials.
Parris was once a bully in the pulpit, demanding more respect and more pay from the members of the church. When we reach the end of the play, Parris is afraid for his life and casting about for a way to redeem the court proceedings.