Do you believe the screenshots?

There was a question - how to verify the authenticity of the screenshots? What can you suggest a way to check if a person and a source are unfamiliar to you, and it’s impossible to give direct links to a page, for example, is this your mailbox?
Ps. In the Ministry of Internal Affairs and other structures, such screenshots are evidence, as are printed pages, for example, of the forum.




Pps. I do not want to say that someone once so deceived someone, just decided to raise this topic.