We are guilty this week of something odd in a Sunday newspaper: we run the same headline on our front page, and we run an editorial on the same subject. We make no apology for doing so. "The Hillsborough Conspiracy" (Part II) follows on our astonishing revelations last week. Those detailed how a police constable's evidence was simply ignored by a judicial inquiry in 1997. His claim – that there was a conspiracy to get officers' stories straight, including wholesale re-writing of their statements – was true, we now know.

Today's exclusive report raises serious doubts about that inquiry even as it was set up. Jack Straw had promised in opposition to look again at the Hillsborough disaster. When he became Home Secretary, he – or, if he prefers, his officials – took just four weeks to conclude that there was no evidence to re-open the inquiry, and he backed them. Was that the best he could do in the face of bureaucratic obstruction, or was he following the line of least resistance? Or had he decided that taking on the vested interest of the police establishment would be politically risky?

Then, having decided the public would doubt this verdict coming from him – or, again, as he would put it, the Government – he "therefore" thought a senior legal figure should be appointed to review the evidence that had come to light since the report of the Taylor inquiry in 1990. Was this simply good government? Was it possible, having conveyed these doubts about a full inquiry to the judge at their initial meeting, that this didn't colour the judge's approach?

Maybe. Perhaps. The families of Hillsborough, though, smell a rat, particularly when Tony Blair had earlier scrawled on a memo from an adviser on the issue of reopening the case: "Why? What's the point?"

We headlined our leading article last week: "Our shame". We believe those guilty of failures which led to the families being denied the truth for 23 years include the London-based media, not excepting The Independent on Sunday. We failed to listen and investigate as we should have done.

Not only does Mr Straw seem to duck his share of responsibility for the scandal, except in the most fleeting of admissions, but he apparently passes most of the blame to Sir Murray Stuart-Smith, the very judge to whom he had said at their first meeting that the Home Office didn't think there should be a new inquiry. As we asked him about the affair, he quickly raised Sir Murray's awful gaffe with the families (a tasteless remark about the families arriving late, as some fans had done at Hillsborough) – the adept deflection of an old master. Had the judge done his job properly, he would have had a public inquiry, said Mr Straw. Not me, guv, has been the refrain of this fiasco.

Where is the humility, Mr Straw? The sense of responsibility from a Home Secretary who promised that he would get to the bottom of it, and who palpably failed? Much more admirable to stand up and say I was wrong and I am sorry. And what of Mr Blair? Just what could that scrawled comment mean?

The Independent Police Complaints Commission will investigate police conduct, including that of Sir Norman Bettison, the Chief Constable of West Yorkshire, and the Attorney General will look again at the inquest verdicts, but who will look at the role of the politicians in this sorry story? We need some answers from them.