You may have seen the video of the 6 year old child being handcuffed in Orlando, Florida. It's been making its way around the inter webs. I've actually researched this issue before, and there was a 2018 case on the handcuffing of a 10 year old here in the 4th Circuit in 2018. I briefly discuss the applicable law, and my opinion. I did a blog post on this on thecivilrightslawyer.com where you can read in more detail, as well as get all the citations, etc.