Will Smith has spoken. Chris Rock has spoken. The Academy has spoken. Even the Los Angeles Police Department has spoken. But the person I really want to hear from has remained silent.

What does Jada Pinkett Smith think of her husband slapping the Oscars host? What was it that caused Smith to switch from laughing at Rock’s joke about her “GI Jane” look to, less than 10 seconds later, striding onstage, slapping him, marching back to his seat and shouting to the stage, “Keep my wife’s name out your fucking mouth”. After which, in case anyone watching might still have thought it was some kind of pre-rehearsed skit, he shouted the same thing again, and twice as loud.

Rock’s gag was personal. Immediately after he said it, Pinkett Smith went stony-faced. She has previously opened up about having alopecia, and how she at first struggled to cope with her hair loss. Were Smith’s actions an attempt to defend her honour? And even if true, why did he feel the need to resort to violence?

Some people have expressed concern at the damage caused by the sight of a Black man resorting to violence. I’m less worried about this. Smith is so mainstream that, in many people’s eyes, he’s almost become raceless. And I’ve never had much time for the notion of role models.

At best, it’s just a meaningless cliche (the idea that, if we stick a Black person on a pedestal, every child will be inspired – no matter the obstacles placed in their way by a system rigged against them). At worst, it’s a stick to beat all Black people with (“Oh no! Look what he’s done! Now every Black child he inspired will turn into a criminal”). Either way, it makes every prominent Black person a permanent ambassador for their race.

Rock has previously taken aim at Smith and Pinkett Smith while hosting the Oscars. In 2016, a ceremony Pinkett Smith had refused to attend due to the lack of diversity among the nominees, Rock said: “Jada boycotting the Oscars is like me boycotting Rihanna’s panties. I wasn’t invited!” He then went on: “Jada’s mad her man Will was not nominated for Concussion. I get it … It’s also not fair that Will was paid $20m for Wild Wild West.” The latter was a critically panned film that Smith had starred in and that he himself has labelled his worst work.

Whatever the history, Smith’s expletive-laden outburst, in a show broadcast to millions of homes across the world, shows a total lack of control on his part. It is also a complete contrast to the family image he and his wife have carefully curated for years.

The couple met during Smith’s days in the Fresh Prince of Bel-Air in the 1990s – a show that endeared him to a generation. Their children, Willow and Jaden, have since become actors and musicians – carrying on the Smith dynasty and attending the Oscars ceremony with them. When Pinkett Smith had an affair with singer August Alsina, she used the admission of her “entanglement” as a point of discussion on her talkshow, Red Table Talk, with Smith present.

On the Oscars stage, this image-protection operation blew apart. This was the biggest night of Smith’s career – the night he should have been revelling in the plaudits after winning an Oscar for his brilliant performance as Richard Williams, the father of tennis superstars Venus and Serena. His speech should have been an acceptance of that honour, and a tribute to that remarkable family, in front of both sisters, who were in the audience. But it came half an hour after that slap, so all the audience were thinking was: “Oh my God, why did he do that?” And, in a hole, Smith immediately attempted to justify his actions by saying, “Richard Williams was a fierce defender of his family.” He went on to talk about having to “protect people”, including, he said, the female actors he’d worked with on set.

What a self-serving display. “To protect” does not mean “to slap someone on their behalf”. This attempt to give violence a bogus morality is at the heart of so much crime. Morgues are filled with the victims of this kind of “protection”.

Smith went on to say: “I look like the crazy father – just like they said about Richard.” Smith has proved himself to be no Richard Williams – a man who faced extraordinary abuse, ridicule and violence while coaching his daughters – and who never once responded in kind. Evoking his name to justify his own actions was the lowest of blows by Smith. Smith’s win should have been an opportunity to highlight Williams’ superhuman drive and self-belief, but instead has become a story about a man’s inability to control his emotions.

I’m sad that, at the pinnacle of his career, Smith has trashed his own reputation. I’m sadder still that, in their own moment of glory, he chose to taint the Williams family too.

• Joseph Harker is the Guardian’s senior editor, diversity and development. He is a former editor and publisher of the weekly newspaper Black Briton