Colleague assaulted, no support from management

[rabelais]

I work in a public facing role and sometimes deal with difficult clients.
One such woman came in to my work last week and kicked off. She was getting more and more agitated until she eventually slapped one of my colleagues across the face, hard. She then ran off before security could apprehend her, though there is cctv. My colleague was in shock I think. She had a livid red mark on her face, and the force of the blow had nearly knocked her sideways. She refused medical attention, and our building closed/work finished for the day shortly afterwards.
I don't work on Wednesday and Thursday, but when I went in on Friday I was told that management are refusing to investigate, or put steps in place to ban this woman, and my colleague has been told she must not inform the police.
I'm outraged by this. To me, this shows a total lack of respect for the safety of staff, and had I been the one to be slapped, I'd have phoned the police immediately - surely the decision whether to or not is not the manager's to take? Unfortunately the colleague in question is the type who if management says jump, she says how high, and she is just meekly accepting this. Meanwhile other staff will still have to deal with this woman.
Morale is already low because of impending reviews and redundancies, but I feel our safety is being put at risk.
What would you do?

It's a difficult one. Your colleague may have reasons of her own why she has chosen not to escalate the matter further.

She may be scared to make a fuss in case it causes problems.
She may not have needed medical attention, that again was her choice.
She may want to hold out for redundancy and has decided to play the long game.

All I'm saying is, by all means support her and make sure she's OK but don't pressurise her to do anything against her will and that could jeopardise her personal employment position.

What support do you want the company to give you and the colleague?

Although there is CCTV you may well find that day's footage has mysteriously "gone missing" if the company is as awful as you say.

my colleague has been told she must not inform the police

Who told her, and did you hear it first- hand?

Have you got a Union Rep you could express your concerns ? - it would be best to do it on the basis of your own personal safety not that of your colleague at this stage.

Don't employers have a duty of care to their employees? And protecting them from abuse, verbal or physical definetly falls under that. I would be incensed that my employers did not give a shit about me. Your colleague has been assaulted.

User149 you are right of course, yes the employer does have a duty of care for a safe working environment. Increasingly nowadays, you see those generic notices on reception desks (where the front line staff are the most vulnerable to abuse) to say that abuse will not be tolerated, action will be taken etc.

It seems like the moment was lost on this one, unless the OP and colleagues are prepared to take a united front, and to ask if CCTV footage could give evidence of the assault

It's difficult if the employee who was slapped doesnt want to take the matter further. But it could be a good starting point to put pressure on the management to take it seriously without necessarily subjecting that person to something they may not feel strong enough to come head to head with management about.

Would be good to get an update from the OP wouldn't it.