What do you think of the practise of shunning in churches and what sort of people carry out this act?

A church in our area uses shunning as a means of getting rid of those who disagree with the pastor. I have read that 15%-20% of protestant evangelical churches practise shunning and that it is on the rise. I have also read that some pastors extract confessions and share what was thought to be a private confession with other members of the church and then use this against the confessor when they are shunned. Do you think this should be allowed? With no legal controls within the church, will this practise open the doors to abuse of church-goers? And, should there be legal restrictions to protect the privacy and rights of the church-goers?