Yes, He Should Have Been Charged

Adrian Peterson of the Minnesota Vikings has been charged for spanking his kid with a tree branch that caused cuts and bruises on the 4 year old child's butt and other body parts.
From ESPN: Minnesota Vikings star running back Adrian Peterson has been indicted by a Montgomery County, Texas, grand jury on charges of reckless or negligent injury to a child and a warrant has been issued for his arrest. The team deactivated him for Sunday's home game against the Patriots....
The Houston station, citing law enforcement sources, said Peterson told police that the incident -- he referred to it as a "whooping" -- occurred in Spring, Texas, in May as punishment for his son pushing another one of Peterson's children. The boy suffered cuts and bruises to areas including his back, buttocks, ankles and legs.   http://espn.go.com/nfl/story/_/id/11514522/adrian-peterson-minnesota-vikings-indicted-child-case
If the allegations are true, then he went a bit overboard.
I have no problem with kids being spanked.
However, when you leave cuts and bruises, especially on a 4 year old, you went to far.
Should Peterson be sent to prison?  No.
Should he get some training on how to punish kids? Yes.
Should his conviction be stricken from his record?  Not sure.
But if the allegations are true, he does need some help on how to punish a kid, especially young kids.  Leaving cuts and bruises is not going to solve a behavior problem, just make them worse.