MELBOURNE lawyer Dan Minogue deals in facts – or at least those that can be proved beyond doubt in a courtroom.

Almost 35 years' experience in commercial law has taught Minogue not to jump to conclusions; that arguments only stand up when backed by evidence.

And this is the precise approach the 57-year-old has taken in a long overdue bid to solve a football mystery involving the famous grandfather from whom he inherited his name.

The original Dan ‘Danny’ Minogue was revered and then reviled at Collingwood.

The popular champion and captain of the Magpies enhanced his hero status while serving in World War I, before enraging the Pies by announcing he would transfer to Richmond.

Minogue's turbulent passage to Punt Road reaped immediate success – he became the Tigers' first premiership coach; and remains the only man to win back-to-back flags in his first two seasons as coach.

In the meantime, an apoplectic Collingwood got nasty, refusing to pay Minogue the provident fund money to which he was entitled, and ensuring his distinctive image couldn't be seen at Victoria Park.

A photograph of Minogue was removed from a veritable wall of fame and banished to a back room, where it was placed atop a cupboard, facing a wall.

It was the ultimate insult for committing what the Pies perceived as the ultimate act of treachery. Indeed, an act that forever destroyed Minogue's friendship with Collingwood coach James ‘Jock’ McHale.

Just what happened to that notorious photo is the subject of some conjecture in the Minogue clan.

The issue centres on two photographs in the possession of the living Dan Minogue – a shot from his Collingwood playing days and an army one, with the latter likely to be the oft-mentioned image in question.

But it's not all black and white. Family members – living and dead – have different opinions on the matter.

"Young Dan" is excited by the possibilities, but his legal acumen tells him there are too many grey areas to be conclusive.

"My gut feel is that one of these photographs is the one that was turned to the wall, but we just can't be certain which one, if at all," he says.