Was that what happened when OJ Simpson was acquitted last year of killing his ex-wife Nicole Brown Simpson and Ronald Goldman? "Did he do it? I don't know. I wasn't there. You weren't there. Only the perpetrator or perpetrators really knows."
Shapiro had asked Simpson just that question and had not taken his initial denials at face value. But, he insisted, Simpson had never deviated from his initial statements. "There is a lot of evidence that points to him. Of that, there's no question. But whether he did it or not, I don't know."
He drew a distinction between "moral justice" ("the ultimate justice, the justice of a higher power") and "legal justice". Simpson might have behaved "absolutely indefensibly" - assaulting his wife and talking in a way "which made your blood curl", but Shapiro insisted in last month's lecture that legal justice had "absolutely and unequivocally" been done in the case. The prosecution had failed to prove his guilt beyond reasonable doubt, he said.
Shapiro claims credit for key elements of the defence strategy which so effectively torpedoed the prosecution's case.
He says he moved swiftly to sign up key expert witnesses - and made a point of hiring those who usually worked for the prosecution. The undermining of prosecution scientific evidence was crucial to the outcome - a fact not generally recognised by those who insist that race was the only issue, he adds.
And it was he who suggested that Simpson's lawyer friend Robert Kardashian (to whom Simpson handed a bag the morning after the killings) should renew his attorney's licence and join the defence, thus ensuring that he was bound by the rules of client confidentiality. (However, in the 38th book to be published about the trial, Kardashian now appears to eschew such professional niceties, and makes a series of potentially damaging revelations about Simpson.)
Shapiro also claims credit for getting the grand jury hearing into the case disbanded. Grand jury hearings, a process for deciding whether a suspect should be indicted, are fatally skewed in favour of the prosecution, he insists. In the Simpson case, this flaw was compounded by the alacrity with which key members of the prosecution team went on television to proclaim his guilt long before any evidence had been analysed.
Shapiro is scathing about the role of the media, generally. It was a case of anything goes, so long as it sells newspapers, he says. The presumption of innocence was abandoned wholesale even by respectable papers. (At one point, The New York Times ended up quoting The National Inquirer as a source because of its desire to compete with the tabloids.) Each day, those involved in the case would run the gauntlet of banks of reporters outside the courtroom, yelling and pleading for a sound bite, any kind of sound bite. "Tell us about your tie; tell us about your suit." At one stage, proceedings were interrupted by the TV interviewer Larry King ringing Shapiro on his mobile phone: "I said to him, 'aren't you watching?'"
Shapiro insisted that the defence's own manipulation of the media was driven simply by the need to level the playing field. For example, although Simpson declined to testify, he made a speech in the courtroom in the absence of the jury purely for the benefit of the cameras.
Despite the vantage position from which Shapiro saw the witnesses - and his apparently unshakeable faith in his client's "legal innocence" - he admits to having been "absolutely shocked" when the jury came back with an acquittal after just four hours.
After a trial lasting nine months and generating 50,000 pages of testimony, he had expected weeks of deliberation leading to a hung jury, divided along racial lines, he said.
Race was an issue; but not the issue, he insists. "I don't believe the Los Angeles Police Department said, 'Let's go get an African-American and frame him.' We found no evidence for that"nReuse content