Johnny Depp was replaced in the new Fantastic Beasts movie (as the same character) by Mads Mikkelsen. Depp's offscreen fall from grace has been going on for some time - he lost a libel suit over domestic abuse allegations - and Fantastic Beasts creator JK Rowling has also come under heavy fire for allegedly transphobic comments. But he's lost industry and public support to such an extent that it's severely damaged his career; she hasn't.

We've also had the slap heard, or at least seen, round the world delivered by Will Smith to Chris Rock at the Oscars. At the time of writing Smith had resigned from the Academy of Motion Picture Arts and Sciences; we will have to see what else happens. Others have been expelled from the Academy: actor Carmen Caridi (for allowing Academy screeners to be released online); producer Harvey Weinstein, actor Bill Cosby and cinematographer Adam Kimmel and writer-director Roman Polanski (all over sex scandals). Weinstein, Smith and Polanski's Oscars were not revoked.

Some who've had allegations made against them - like director Bryan Singer and actor Kevin Spacey for sexual assault and Mel Gibson for anti-Semitic and racist tirades and domestic abuse - have been "cancelled" despite neither having had any criminal convictions. Gibson is clawing his way back: his 2016 film as director, Hacksaw Ridge, received six Oscar nominations (including one for director) and was a hit and he's been on screen again. Spacey's footage was removed from All the Money in the World and his role reshot with Christopher Plummer. Spacey and Singer haven't had credits since (in both cases, young men were involved: might this be a factor?).

Polanski pleaded guilty to unlawful sexual intercourse with a 13-year-girl in 1977 and fled overseas while on bail. His career continued in Europe and he won a best director Oscar for The Pianist (2002).

The #MeToo movement has been part of a trend in recent years to highlight wrongdoing and have consequences meted out for what has long gone ignored or been hidden - hence the recent Academy expulsions. While the aim is laudable, sometimes pillars of the justice system, like the presumption of innocence, are ignored.

"Cancelling" is not new, though the reasons for it might sometimes have differed in the past.

Silent comedy star Roscoe "Fatty" Arbuckle was tried three times on the charge of fatally rupturing a woman's bladder during sex. He was acquitted by the third jury but banished for a while by a film industry trying to dodge bad publicity and government control. His career was badly damaged.

Sexual and other abuses were common in the old Hollywood studios whose power meant scandal was often averted through money or influence. Extramarital affairs, "living in sin", and ex-nuptial children - as Ingrid Bergman, for one, discovered - were scandalous: nowadays they seldom raise an eyebrow. Sometimes it's hard to keep up: Elizabeth Taylor went from grieving widow to brazen hussy when she "stole" Eddie Fisher from Debbie Reynolds, to winning an Oscar when she almost died, to causing more scandal when she left Fisher for (the married) Richard Burton. But she endured.

A cynical view of "cancelling": money matters most in Hollywood. If people's alleged or proven words or actions are thought to be likely to cause too much financial damage, then they will be shunned.

Maybe the same rule applies in Hollywood as it does in politics: don't get caught.