I fully support any attempts to damage the Daily Mail and agree with the petition's goal.
However, I don't think that firing Littlejohn will go far enough. If he loses his job, another bigoted right-wing rag will hire him, offline or online. And the Daily Mail has no shortage of racist, sexists, homophobes, and other forms of prejudiced jerks.
The Meadows family should pursue a lawsuit. I don't understand how British law works, but Lucy Meadows was not a public figure and The Daily Mail was encouraging people to invade her privacy to the point where it impacted her life.
A more karmic form of punishment would involve doxxing Littlejohn. If he enjoys snooping into people's private lives, then others should extend the same hospitality to him.