Joan Smith: After Marlon King, kick sexism out of football

Until last week, Marlon King was just another overpaid Premier League footballer. Now he's in prison after being found guilty of a brutal assault on a student, and he's been sacked by his club, Wigan Athletic. The footballer is 6ft 1in, his victim just over 5ft, and she's still recovering from her encounter with a man who clearly can't control himself around women.

When she felt him grope her bottom in a nightclub and turned round to object, King retorted that he was a millionaire. "You're not even in my league," he sneered, and smashed her to the ground with such force that he broke her nose, split her lip and gave her a black eye.

On Thursday, at the end of his trial, the wealthy striker was ordered to pay the woman £3,125 compensation and register as a sex offender.

King has a string of criminal convictions and has been in prison before – not for assaulting women, but for receiving a stolen BMW. On that occasion he was jailed for 18 months, but it was reduced on appeal and he served only five months. He's also been convicted of (among other things) drunk-driving, theft from a vehicle, using a cloned credit card, head-butting a football opponent, and two previous attacks on women.

In June 2003 he admitted assaulting two women in Soho, punching one of them in the face and pursuing them with a belt wrapped round his fist; he was fined £1,000 and ordered to pay £250 to each victim. In January 2006 he approached a woman in Leicester Square, smacked her on the bottom, slapped her head and spat on her; he was fined £300 and ordered to pay £1,000 compensation.

The latest attack was in December last year when King was celebrating scoring a goal and – what a charmer – news of his wife's third pregnancy. And the truly amazing thing is that despite his appalling record, he's been given exactly the same sentence (18 months) for sexual assault and actual bodily harm as he got for driving a stolen car.

Hello? Is anybody in the criminal justice system listening? I am only just resisting the temptation to use block capitals: this man is a danger to women. He is in denial about his violence towards them – he claimed at his trial that he was a victim of mistaken identity, and his agent says he intends to appeal – but he has been in court often enough to expose his true character.

King is the kind of serial offender the government has promised to deal with harshly, and he appears to qualify for the indeterminate sentence of imprisonment for public protection (IPP) which was introduced in 2003 to deal with defendants who have committed a serious violent or sexual offence and pose "a significant risk of harm to the public". That is exactly how I'd describe a man who makes a habit of groping and punching women in public places.

But it's not only the criminal justice system that has questions to answer following this case. Professional football in this country has a terrible reputation for misogyny, but the authorities are reluctant to crack down in the way they have against racism; well-known footballers celebrate victories by filming each other having group sex ("roasting") and organising parties which sometimes lead to allegations of rape. It's the behaviour of spoiled, immature young men who regard women with contempt and believe they're above the law. How long do we have to wait before influential clubs like Manchester United and Chelsea join forces with the FA to Kick Sexism Out of Football?