It does appear that Peterson went overboard and most likely has anger management issues... BUT what the hell does Peterson beating his kids have to do with other parents beating theirs? Who the hell are some of you to tell others how to discipline their kids? Timeout don't work in some households.
Some people still believe in the bible. The bible is a pretty good book on how to live. Here are some bible verses.
"Chasten your son while there is hope, And do not set your heart on his destruction." (Proverbs 19:18)
"Foolishness is bound up in the heart of a child; The rod of correction will drive it far from him." (Proverbs 22:15)
"Do not withhold correction from a child, For if you beat him with a rod, he will not die. You shall beat him with a rod, And deliver his soul from hell." (Proverbs 23:13-14)
"The rod and rebuke give wisdom, But a child left to himself brings shame to his mother...Correct your son, and he will give you rest; Yes, he will give delight to your soul." (Proverbs 29:15,17)
"You shall not withhold your hand from your son or from your daughter, but you shall teach them the fear of God from their youth..." (Didache 4.9; Barnabas 19.5)
Should I look to all the liberal, we did a research study, give everyone a trophy crowd on how to discipline my child. Or maybe look at what the bible says?
The word Rod in the bible is actually Hebrew for a Shebet which is a small tree trunk that was a shepherds staff carried by the head of a family. Go look at the movie The Bible with Charlton Heston when he played Moses and see the cane he carried for reference. The father would spank their kids with this stick and it hurt and left marks. It was also used on sheep and to protect them from predatory animals.
I personally think every kid is different. As a parent you have to discipline them with what's the most effective. A 2 year old does not understand reason, probably not a 4 year old either, a pet certainly doesn't. I think it is much more effective to spank kids when they are young. You don't have to spank them hard either, use a folded newspaper where the noise from the rustling papers make more commotion than the actual contact. I would never use an open hand because that could injure a child if hit in the wrong place. You could hurt a kids hip or back swatting them in the butt. Nonetheless, I can't tell someone how to spank their kids.
Some cultures are very serious in their discipline. Go look up caning in some Asian cultures. The liberals want to convince you that 21st century discipline is to reason with a 2 year old or put them in timeout. Good luck.