THE ONLY men in Scotland who don't support Celtic or Rangers are referees, assistant referees and football journalists. It is a happy coincidence that these noble, upstanding types were born and raised in a protective bubble of immunity, making them impervious to the charms of the Old Firm.

For much of the country, especially the west central belt, an allegiance to one of the big two is in the DNA, but not for the refs or the writers. No sirree. Every Saturday afternoon our press boxes are full of people who support only the likes of Partick Thistle, Airdrie or St Mirren.

And you'd better believe it. As for the refs, well, none of them ever really followed any one team when they were growing up, you understand. They just liked whoever played the best football. Of course they did.

Given the suspicion, negative reactions and hounding they would attract by owning up it is quite understandable that referees and their assistants, and even mere hacks, keep their traps shut about the fact that they may have spent their formative years paying into Parkhead or Ibrox.

Graham Roberts secured big, bold headlines at the launch of his autobiography last week by announcing that there were referees freely walking the streets of Scotland who, brace yourselves, support Rangers or Celtic. Apparently they're not even under any supervision orders or electronically tagged.

Well, yes. Of course they are out there. Most people interested in football in this country support one of those clubs. The single most significant and depressing factor which prevents the top flight in Scotland being more than an endless duopoly is the huge, unalterable gulf in fanbases and attendances between the Old Firm and the rest.

From any 10 people interested in football in Scotland maybe six will support Celtic or Rangers (or more than six, depending on geography). Scottish referees are a product of the same background and social conditioning as the rest of us. As Scottish males enthusiastic about football, some of them being Old Firm fans is as inevitable as breathing oxygen.

Roberts went further, of course: not only did Scottish referees support Celtic or Rangers, they made decisions which demonstrated their active bias towards whichever club they favoured. That was why, in his view, foreign officials should be asked to handle the Old Firm derby.

Roberts' infamous conducting of the party tunes at Ibrox made the Southampton-born former England international an unlikely advocate of the impartiality to be expected from those with no previous connection to Scottish football.

But his comments about bias were meat and drink to the conspiracy theorists who convince themselves that this or that official is working against their team. Walter Smith weighed in too by alluding to two decisions given in Rangers matches by Tom Murphy.

The assistant referee kept his flag down when Scott McDonald scored for Celtic in a derby in April, and raised it when Steve Davis played a pass to Kris Boyd at Motherwell on Wednesday. Both decisions were wrong, marginal and explicable.

Smith offered a clarification two days later when he said he had no problem with Murphy being on duty at future Rangers games, but his initial innuendo meant the hounds had been released. Murphy is now seen by some Rangers fans as a guy who has it in for them and gives Celtic every break he can.

It would be sort of exciting to believe, and write, that referees go out with an agenda to help Celtic or Rangers, but I don't buy it. Endless replays, multiple camera angles, slow motion and the internet mean they can't hide like they used to and any blatant demonstration of prejudice would mean instant, permanent and deserved notoriety.

Are they prone to errors? Naturally, and they prove that every week the same as the rest of us in all walks of life. Are they influenced by the noise of the vast home crowds in Glasgow? Sadly human nature dictates that they will be. Are some of them closet Celtic or Rangers supporters? Certainly, but the last time anyone checked that wasn't a crime, nor a reason to exclude them from serving in the SPL.

The real issue here is the hysteria of tight, incorrect offside decisions being treated as though a linesman ran on to the pitch to make a sliding tackle. Ironically the one man whose agenda was undeniable last week was Roberts.

As Smith said in his best quote of the week: "It's not a bad line if you're trying to sell a book."

However long he lasts in the job, and however well he does in it, just about the only certainty is that Diego Maradona is going to brighten up our lives when he arrives with Argentina this week.

I expect the works from Diego, the full unbridled Maradona experience. So take out a pen and tick off the following checklist as he delivers them: 1. being surrounded at Glasgow Airport; 2. pretending not to hear questions; 3. crying; 4. wrapping himself in an Argentina scarf (or a Scotland one); 5. saying something about how good our fans are; 6. saying something mildly derogatory about England; 7. looking over-excited, wide-eyed and slightly baffled; 8. offering praise for Kirk Broadfoot or Chris Iwelumo; 9. promising to come back to Scotland very soon; 10. resigning.

It's going to be great.