Sensationalist media claptrap is spoon fed to the masses on a daily basis and gullible people like our 'anti establishment' ellal slavishly believe in every word.
A crook carrying a gun gets shot. How is that a bad thing?
The jury believed he was in possession of the gun, but lobbed it away, and was not in possession of it, when he was shot by the rozzers.
Therefore, the finding of "lawful killing" makes no sense.
FWIW, I too don't think that the police should be Judge Dredd; however, the world is in shades of grey, whereas the wording of the Law is not.
Hypothesising, Duggan's tossing away of the gun (which was only 20ft away - a three yr old could have thrown it as far, so he hardly had to take a run-up). Could have genuinely been surrendering, and been executed. Not lawful killing.
Could have genuinely been surrendered, and the rozzer panicked. Not lawful killing, but perhaps mitigable to some degree.
Could have genuinely been surrendering, but (badly, for himself) drew the gun across the rozzer's line, during the toss-away, so rozzer (under threat), shot him. Not lawful killing, but perhaps mitigable in some part.
Could have been levelling to shoot the rozzer, got there too late, and the gun was flung from his hand by him recoiling from the bullet. Lawful killing, but nigh-on impossible to prove.
We'll never really know.