Literally.
They are not simply not allowed to, as an email edict from Fox News Washington managing editor Bill Sammon to all Fox News producers now proves:
From: Sammon, BillThis happened during reporting on the pivotal climate change conference, COP15 Copenhagen, in December 2009. The "controversy over the veracity of climate change data" Bill was referring to here is the 'Climategate CRU hacked emails scandal' that was much puffed-up by biased media outfits like Fox News as evidenced of a disinformation conspiracy by climate scientists, and subsequently debunked all too late.
To: 169 -SPECIAL REPORT; 036 -FOX.WHU; 054 -FNSunday; 030 -Root (FoxNews.Com); 050 -Senior Producers; 051 -Producers; 069 -Politics; 005 -Washington
Cc: Clemente, Michael; Stack, John; Wallace, Jay; Smith, Sean
Sent: Tue Dec 08 12:49:51 2009
Subject: Given the controversy over the veracity of climate change data...
...we should refrain from asserting that the planet has warmed (or cooled) in any given period without IMMEDIATELY pointing out that such theories are based upon data that critics have called into question. It is not our place as journalists to assert such notions as facts, especially as this debate intensifies.
The catch-all "critics" turn out to be fossil-fuel funded think-tank spokesmen, such as American Enterprise Institute's Kenneth Green. Not peer-reviewed climate scientists.
And, the rest is rather depressing history.
Global Warning Climate Change Energy