Usually, it's pretty easy to determine what's "fake news." However, with this news outlet, I can't tell. Based on the titles of their articles and an answer to my previous YA answer question which sourced them, their political views seem to closely match my own, but this doesn't necessarily mean everything they say is true.
Have any major news outlets ever sourced them? Are there any of their articles blatantly fallacious or have proven to be untrue?
No one from Counterpunch.org was ever on C-Span Washington Journal. At least, not when I watched (haven't had cable in years). This is definitely a red flag. However, it could just mean they weren't popular in 2013 and earlier. Their website says they've been around for 25 years though.
Although I'd like to believe Counterpunch.org, I'm unable to vet them. I do plan to read articles from them, but am seeking a third party opinion before I do.
If there are any more criterion pertinent to determining the validity of a news source, not mentioned above, I'm all ears.