That seems illegal, which illustrates the point well enough already.

Legally? Maybe not. But ethically and morally? Hell yes!

We need a Robin Hood of privacy. Extralegal justice for the common people, for whom official channels are contemptuous.

What if you were mistakenly or maliciously targeted?

If you wish to avoid vigilante justice, you need to provide something better. The government is meant to handle matters like this to protect anybody who might be wrongly accused, but the government is abdicating their duty to do so. When the government abdicates their duty to the common people, the common people have a moral and ethical right to take matters into their own hands.