You have a really odd idea of how journalism functions.
That's why every single 'controversy' and news story ends up on every media site under the sun.
Plenty of journalists have experience in the fields they cover (check out the SCOTUSblog's publisher's bio, for example: http://www.scotusblog.com/author/tom-goldstein/) and the longer they cover a particular beat the more info they get about the field they're covering.