How noble that Thames Valley police has let it be known that its misconduct-in-public-office investigation into Andrew Mountbatten-Windsor is also considering potential offences including corruption and sexual misconduct. On Friday, it made a public appeal for potential victims and witnesses to come forward.

Obviously, the best time for the police to have started quietly asking questions was shortly after Metropolitan police officers – Andrew’s close protection detail – ferried him back from a London nightclub to a house with some other friends in their 40s, and one young-looking 17-year-old girl. Then waited outside till he decided it was time to come home. But as the saying goes: the second-best time is now. No wait, the second-best time was probably when Andrew paid a reported £12m to settle out of court with Virginia Giuffre, despite maintaining he had no recollection of meeting her. (He denies any wrongdoing.) Ach no, the second-best time was when leaked emails suggest the former prince passed his Met close protection officer Giuffre’s birthdate and US social security number and asked him to carry out checks on her. Sorry, wrong again, the second-best time was a full 12 years ago, when Giuffre alleged that she was sex trafficked to and assaulted by Andrew on that night mentioned above, as well as on two other occasions.

What are we supposed to say now? Well done, officers? Better late than never? Do me a favour. Virginia Giuffre took her own life just over a year ago at a remote Australian farmhouse, unable to outrun her demons. She was 41. But she spent a really, really, really long time – almost a third of her life – trying to get people to act on what she was saying about a man who was literally protected by serving law enforcement officers. The Met never opened a full investigation into her claims.

You hear a lot about pressure on policing numbers and the inevitable downstream effects on service delivery. But imagine if you had a minimum of two police officers literally on the scene, often inside the house, in a whole variety of “odd” situations all over the world, with nothing to do but watch and wait for hours on end, and who might very well have passed the time wondering what His Nibs might be up to, or – to pluck an example – why they were being asked to provide private security for a dinner party at the New York mansion of a man who had recently been released from prison after serving time for soliciting prostitution from a minor. Did anything about what these serving officers were required to do ever strike them as weird and perhaps even potentially legally undesirable? Of course it must have. Did they or their superiors do anything meaningful about it? Of course they didn’t. Andrew’s various homes were only finally searched in the year 2026, and evidence of interest was reportedly recovered during those probes.

The sole reason certain individuals and institutions in the British establishment have become relaxed about treating this case as they should properly have done all along is that not doing so would now be more damaging to them. But they spent the best part of 15 years not doing so. Nothing about this has ever been about doing “the right thing” – it has always and only been about protecting their vested interests, and that goes for the monarchy as much as the police. And it also goes for the politicians who seem to have spent for ever accepting guidance or winks and nods about how things just have to be, and not demanding that actually, this was bullshit and things shouldn’t be like that at all.

As far as the police go, it remains a grimly fascinating possibility that they waited for Andrew’s mother to die before properly grasping this nettle. According to various solicitous statements on Friday, they believe there might be other witnesses or people with helpful information out there. Gosh, after all this time, I don’t know where you’d start. Met police employment records?

It was the late queen, we now know, who pushed so hard for Andrew to get the trade envoy role, presumably to keep him out of trouble. Great job! etc. Looking back to one column I wrote in 2015 (long time covering this subject), I mentioned that I’d always assumed that job “was merely some sinecure designed to get the queen’s second son between golf courses without any boring little people making a fuss about who was paying for the helicopters”. And yet, according to the Andrew papers released this week, his people seem to have actively tried to prevent him playing golf on his overseas jaunts. As one brief states: “Captain Blair [Andrew’s then personal private secretary] particularly asked that the Duke of York should not be offered golfing functions abroad.” Oh dear. There’s a reason why football managers and trophy wives – and, apparently, concerned royal mothers – prefer it when their headstrong charges are playing golf. And that is because when they are doing that, they are not doing any of the other “things”. What were you thinking, Captain Blair?! Andrew should ALWAYS have been golfing, because if he wasn’t doing that, there seems to have been a strong chance that he might have been cocking up Britain’s interests, laying the ground for impenetrable private business deals or indulging in various other activities that are even less mentionable.

No doubt we shall be hearing much more from the police about what is continually referred to as an “unprecedented investigation”. But you know what’s better than an unprecedented investigation? A precedented one. This one should absolutely have been precedented, and doing it now – for the public service equivalent of clout – is precisely nothing to boast about.

• Marina Hyde’s new book, What a Time to be Alive!, is out in September (Guardian Faber Publishing, £20). To support the Guardian, order your signed copy at guardianbookshop.com. Delivery charges may apply.

• Marina Hyde is a Guardian columnist

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