Parenting and discipline across cultures

From the CERIS (Centre of Excellence in Research in Immigration and Settlement) website, a post about parenting across cultures, as discussed in a television show, featuring CERIS Director Dr. Mehru Ali on parenting and discipline across cultures):
“Ali talked to TVO Parents about the cultural aspect of parenting and discipline in a Canadian context. In an expert panel to introduce a new TVO series The Slap, Dr. Ali shared her perspective and research on parenting and the situation that newcomers find themselves in a new society with potentially different norms. She emphasized that cultural norms greatly differ among groups and that we must consider the diversity of parents before judging one type of discipline over another”.
Ali comes in at about six minutes into the video. She addresses the discipline issue of hitting children. Increasingly, physically hitting a child is becoming unacceptable but Ali says we need to “consider” different parenting styles. Ali wavers on whether physical force is ever warranted but says the key principle is to keep the child protected.  My question is how do we reconcile types of discipline, though, with Canadian norms and laws? The host of the show cites that about 20 countries have banned corporal punishment. Canada, as a signatory to the UN Convention on the Rights of the Child, and Article 19 (see below), have a legal obligation to protect children from physical violence, whether it’s from a parent or not.
Article 1. States Parties shall take all appropriate legislative, administrative, social and educational measures to protect the child from all forms of physical or mental violence, injury or abuse, neglect or negligent treatment, maltreatment or exploitation, including sexual abuse, while in the care of parent(s), legal guardian(s) or any other person who has the care of the child.”