The BBC refers to the killer as a "terrorist".

Here's probably the most the BBC reported on his mental health issues;

http://www.bbc.co.uk/news/uk-38071894

A person known to have severe mental illnesses, was labelled as simply a conservative because he killed a liberal MP.  The liberal media complete refused to mention his mental illnesses.

Mentally ill’ or ‘terrorist’? Jo Cox assassination exposes media bias
From RT
June 20, 2016

The language used by the media and government officials to describe the alleged assassin of British MP Jo Cox has been criticized for highlighting his “mental illness” and not referring to him as a “terrorist.” Thomas Mair, 52, has links to neo-Nazi and white supremacist groups and reportedly shouted “Britain First” while he stabbed, shot and reportedly dragged Cox down the street by her hair. The Sun referred to Mair by his name or used adjectives like ‘white supremacist’, ‘terrorist’, or even ‘mentally-ill loner’. These characterizations did not go far enough for some on Twitter, who asked whether there was a double standard held by the media:

• "The singularly sensitive way that the media treats violent white men is beyond cliché at this point."
          Reed F. Richardson (@reedfrich) June 17, 2016 pic.twitter.com/fixp8lO5eo

• "Why hasn't MP Jo Cox's killer been branded as the terrorist that he is…Family Guy has the answer (as always)!"
          James Johnson (@James___Johnson)  June 18, 2016 pic.twitter.com/emeY2E5jWH

• "Freedom fighter, terrorist, lunatic? And what if he would have been a muslim?"
          Tammo ter Hark (@TammoterHark) June 18, 2016

• "Seems the Daily Mail are a lot kinder to decent white British terrorists"
          JulietteAdAstra (@JulietteAdAstra) June 18, 2016 #ThomasMairpic.twitter.com/GSRdXupoga

A person known to have severe mental illnesses, was labelled as simply a conservative because he killed a liberal MP.  The liberal media complete refused to mention his mental illnesses.

Now you want us to look for a mental illness because the shooter was a liberal, rather than simply being liberal shooter.

Hypocrites, the lot of ya.

Hmm.

The US shooter is "crazy" because he attacked conservatives.

The UK stabber that killed MP Jo Cox was an "alt-righter", even though he was a known nutter with severe mental issues.

Did you even watch the video? The person is arguing that nobody is asking, what medication was the shooter on? He clearly suffered from mental illness, as he had sold off most of his assets prior to the shooting.

In the video, the person gives a critic on the mental health problem plaguing America; The pharmaceutical industry, and how drugs are advertised to "make you better", but they often just end up making you worse.

The US shooter is "crazy" because he attacked conservatives.

The UK stabber that killed MP Jo Cox was an "alt-righter", even though he was a known nutter with severe mental issues.