There is a long, long history of research into the grim effects of corporal punishment in child-raising. As a starting point, see the widely cited 2002 meta-ana

There is a long, long history of research into the grim effects of corporal punishment in child-raising. As a starting point, see the widely cited 2002 meta-analysis by Gershoff [0] as well as this other meta-analysis they did more recently which I am less familiar with [1]. I also highly recommend going through the research work of the late Murray Straus at the University of Wisconsin [2] who spent much of his time systematically analyzing how spanking harms child development in just about every single way you can imagine. [0] Gershoff, E. T. (2002). Corporal punishment by parents and associated child behaviors and experiences: a meta-analytic and theoretical review. Psychological bulletin, 128(4), 539. [1] Gershoff, E. T., & Grogan-Kaylor, A. (2016). Spanking and child outcomes: Old controversies and new meta-analyses. Journal of family psychology, 30(4), 453. [2] https://en.wikipedia.org/wiki/Murray_A._Straus https://en.wikipedia.org/wiki/Murray_A._Straus