By definition, celebrities are people who are often on TV or in the paper. Having a constant media presence extends the celebrity's profile beyond their core field of endeavour, thus multiplying their earning power. The celebrity becomes a brand.
So far, so good if you crave attention and sincerely want to be rich. But in return the celebrity gives up the right to privacy, which is why we should ration our sympathy when stars who use the media to flog their movies or records or cookbooks spit the dummy when photographed without makeup or push-up bras, or canoodling with someone other than their significant other.
The second fish hook in this deal with the devil is that the media will chart the celebrity's fall from grace with as much enthusiasm and gratuitous detail as it celebrated their rise, and an added dash of malicious glee.
Or, in this instance, "alleged" fall from grace.
Some of the commentary that has accompanied the courtroom claims of Lawson's drug use is proof that where there's a will to stick the boot in, there's no such thing as the presumption of innocence.
The most nauseating example was a column by the Daily Telegraph's Allison Pearson, which was picked up by Fairfax papers here and in Australia.
After a mealy-mouthed, more in sorrow than in anger "I adore Nigella as much as the next person" preamble, Pearson embarked on a methodical hatchet job on the premise of "what if it's all true?"
Two of her hypotheses went well beyond the bounds of decency.
"Heaven knows," she wrote, "what the Lawson of the Diamond years would make of the woman and mother she is said to have become." The Diamond in question is Lawson's first husband John, who died in 2001, aged 47. Actually the answer doesn't reside in heaven: Pearson herself addressed this very question earlier in her piece. After pointing out that Lawson lost her mother, younger sister and husband to cancer, she conceded: "If Lawson did turn to painkillers or drugs at this point, all I can say is that she had an awful lot of pain to kill."
(In testimony Lawson admitted to taking cocaine half a dozen times with Diamond when his disease was in the terminal stage because "it gave him some escape".)
Pearson also speculated, without providing a skerrick of justification for doing so, that when an unnamed friend of Charles Saatchi claimed Lawson had failed to keep a promise to her ex-husband, it was that she'd stay off drugs.
Referring to the infamous photographs of Saatchi grabbing Lawson by the throat and nose outside a London restaurant, Pearson asked, "What if that tweak on the nose was not aggressive and patronising, as we all supposed, but a dig at her cocaine habit?"
Given that the cocaine habit is thus far an unsubstantiated allegation made by former assistants on trial for fraud, using it to recast Saatchi as a long-suffering victim is premature, to say the very least. (Saatchi himself has made a turbo-retreat from the incendiary "Higella the habitual criminal" email that unleashed the hounds.)
And as a rebuttal of Pearson's column pointed out, "even if Lawson turns out to be drug fiend of epic proportions, it doesn't have any bearing on her right to be protected from violence and assault".
For what it's worth, I tend to believe Nigella.
Lax though he was in keeping track of household spending, even Saatchi would have noticed if Lawson had been feeding a full-blown coke habit over a period of years. As Robin Williams observed: "Cocaine is God's way of telling you you've got too much money."
