Ban encryption to protect the children? Help to research on whether that is true

I've come across this article on Who is being monitored? - https://tutanota.com/blog/posts/wer-wird-belauscht - which shows figures from German surveillance orders being used mostly for drug-related crimes. I would like to do a global collection on such figures for wikipedia as I think this is direly needed to make an argument again the 'But we must break encryption to protect the children'. For this, I need information like * Where could I find surveillance orders figures for your country? * How are the surveillance orders called in your country? * What are the authorities that need to publish such figures? Any help would be greatly appreciated!