The UK online political discourse leading up to the election is so fucked, we might as well give up and declare truth dead.

For instance, take the knife attack mentioned in the article, which was carried out by a convicted terrorist who'd been released from prison. Prominent Labour MP* Yvette Cooper blamed the Tories for his release in a popular viral Twitter thread: https://twitter.com/YvetteCooperMP/status/120076129489225728...
Her claims are lies. She claims that the new arrangements which replaced Labour's IPPs failed, but they didn't apply here - he was sentenced under the old rules which still had IPPs rather than their replacements. She claimed that the Appeal Court said that his release should be left to the Parole Board and blamed the Tories for the fact that it wasn't. They didn't say that, and it was a law passed by her party in 2008 which meant the Parole Board had no say. She implied the Tory replacement for IPPs allowed serious criminals to be released early without parole board assessment, when in reality it reinstated the parole board involvment Labour had removed. There's a good summary here which backs up all of these facts: https://thesecretbarrister.com/2019/11/30/10-thing-you-shoul...

So naturally, some Tories went after those claims - and the legal blogger who wrote the summary I've linked above promptly attacked their debunkings and not the original Labour claims, and that went viral too: https://twitter.com/BarristerSecret/status/12008087678200463... In fact, that blog post above was written to specifically back up his claim that the Tories were liars. (He's technically right - that tweet is a little misleading, since the courts could avoid automatic release by imposing the IPP sentence that Yvette Cooper had falsely claimed the Tories had stopped them imposing - but it's pedantry. The claim being debunked was about what the Parole Board could have done after that sentence was handed down. That omission mostly just means the Labour claims were even more false than suggested.)

It gets better. Tory PM Boris Johnson wrote a 16-tweet thread so pedantically accurate and in line with his own claims that he couldn't discredit it as inaccurate anymore - so instead he accused Boris of stealing that blogpost which he'd written to debunk the Tory lies, implying this made the Tories the dishonest ones falsely claiming those facts supported their side: https://twitter.com/BarristerSecret/status/12010764392500879... (Note he never technically said Boris was lying, just that it was "weapons grade shithousery"). He even used the fact that they both debunked that false claim about the Appeal Court - one which Yvette Cooper had made but the Tory debunkings had not - to back up this argument. Along with the fact they both linked to literally first answer you find when searching for information on parole for extended sentences. It turns out that thanks to inattentiveness and partisanship, you can not only convince people of the exact opposite of what your own evidence shows without technically lying, you can make them believe that the people who don't believe that are the ones who've been suckered.

Meanwhile, the BBC's coverage was vague he-said she-said stuff which didn't check anything, and the Guardian was (and still is) repeating the debunked claims. (I think they did eventually write an explainer which debunked most of the claims whilst carefully avoiding tying them to any party, but I can't find it lately.) Also, the more recent BBC headlines all insist that Boris Johnson is the one who politicised this act of terrorism.

* Technically there are no MPs since Parliament is dissolved for the election, but that's pedantry.