Lists like this are great material for investigations, thanks for sharing! I guess there's a chain of reasons why the law enforcement involvement isn't being investigated:

• Law enforcement is unwilling to shoot itself. Obvious.
• On the next level (organization responsible for internal investigations on them), they must be aware of the problem but nobody would benefit from such investigations financially. They benefit more via covering it up (corruption)
• On the yet higher level (congress), they again must be well aware of the issue, some might even open their mouth about it, but they have several issues preventing the actions to take place. Like for example: Friends inside to protect, fear of loosing status or career, already being blackmailed/corrupted/involved etc.
• On the yet higher level (WH), the reasoning follows as similar but goes even deeper due to their connections. Simple form: If you managed to get this high, the drop is more fatal. Better to just keep your mouth shut or join the crime. People with high moral have an issue here, and they are potential whistleblowers. People with low moral are potential to fall under corruption. Mutual trust might even be sealed with a video on child rape on each other.
• On the yet higher level (financing, meaning Koch brothers, Soros, Rotchild, Wyss, Gates etc billionaires financing politics) there's no reason to work against this problem, as it would only prevent financing from it. These instances are mostly friendly towards any dualism in the society, including far reaching phenomenons like wars, conflicts, catastrophes, drug/human trafficking, as these are seen as sources of income in general. Of course they do talk against them to maintain their status and public acceptance. Also on this level, mutual trust might even be sealed with a video on child rape on each other.
• On the possible even higher level (religious, spiritual conspiracy) the persons in the high financial level could be seen a servant to a greater evil. This is a theory always gathering interest among some pizzagaters, mostly in a purpose to try to understand how such crimes against humanity could ever be possible. I mean, who the hell could rape or torture a child? One possible answer is in the question - the hell.

Dropping to the level we work on, we do investigate. Citizen journalism being a grass root movement which nobody else but other citizens (and few high moral individuals from the above mentioned levels) are interested to support or finance, lists like this are so important, once again thanks to the OP.