This is what happened on the A90 (Kingsway West) Dundee, at around 5:30pm on 15 June 2004, according to the Crown’s 'witnesses'.

My comments are inset.

Improbable events are highlighted in green.
Locations A to F can be found on this  Kingsway map.

Location A
At the A90/A85 junction (Swallow roundabout), my car swerved into the path of a Kawasaki motorcycle.

Unusually for a motorbike, it stayed behind me

all the way to the next (Myrekirk Road) roundabout,

1.3km further on.

At the Myrekirk Road roundabout, the bike joined a queue of traffic doing 50mph in the outside lane and the riders watched me race up the empty inside lane at well over the speed limit - 60mph was mentioned.
Location B
Around 400 metres from the roundabout, the motorcyclists saw me swerve into the path of an Astra in the outside lane.

This would put the bike close to, and just 

behind, my car.

Carnegie, the Astra driver, confirmed this, saying there was a bike nearby just as he was forced to brake and swerve to avoid a collision.

If the bike was right behind me at the roundabout,

it could not possibly have been right behind at

the locus of an incident 400m further up the road,

given the claimed speed differential of about 10mph.
No, it would have been around 60 metres back,

behind several other vehicles that would have

obscured the bikers’ view.

After the incident, Carnegie said I overtook him again, but conceded that he was mistaken after the Sheriff asked: “How does it pass you again if it’s already in front of you?”
Location C
The bike, which had stayed behind both cars, passed the Astra (giving its driver a thumbs-up sign), then passed my car (near an underpass at the junction with McAlpine Road).

The bike would have been ahead of both cars at

the next location:

Location D

I undertook the bike on the inside, near Charlotte Street.
Carnegie also passed the bike (on the inside) as he prepared to leave the A90 at the next roundabout. He acknowledged the riders with a thumbs-up sign.

He'd earlier told the court he'd had no
contact with the riders.

Location E

The biker confirmed that my car was "in front" of him when he gave the Astra driver the thumbs-up sign on the approach to the Strathmartine Road roundabout.
He then said he'd identified me when I "looked over and we looked back".

So, my magic Citroen was simultaneously behind 

the bike and ahead of it.

When questioned by the Sheriff, Carnegie said he wrote down my reg number just before he turned off at Strathmartine Road, presumably just before I carried straight on.

The performance of these three tasks – preparing
to leave the Kingsway, acknowledging the riders,
then writing down a reg number whilst driving –
might seem like a tall order for a man who was,
as he claimed, confused and traumatised (“he looked
shaken,” reported the biker) by the recent 'incident'.
He would have had all of 5 seconds to accomplish these
three tasks.

Location F

The pillion passenger said that after Strathmartine Road, I undertook the bike again at a location she did not specify.

The bike driver / rider had earlier told the court
that my car was in front of them.
Nobody in the courtroom noticed the discrepancy.

The bike then passed my car just after Clive Road (4.2km from Myrekirk Rd).
The rider stated, when answering the Depute’s question about the manner of my driving, that I “wasn’t hanging about”.

This suggests I was driving at well over the 50mph
limit (Carnegie had earlier estimated my speed as
"at least 60mph").
Therefore, the biker himself must have exceeded
the limit by some margin in order to overtake me.
And yet he consistently maintained that he was
riding at "up to 50mph".

Notes on an Improbable Drive
1) According to their testimonies, the Crown’s 'witnesses' had my speeding car in view over the entire distance between the Swallow roundabout and the Strathmartine Road roundabout, 5.3km in all.
Other than the 'queue' caused by the broken-down white van, they mentioned no traffic hold-ups that would have allowed them to catch up.
Logically, if I were a reckless driver charging along the A90 at excessive speeds, they must have been doing likewise to keep me in view.
But they testified that they were not speeding – they were driving at, or "up to 50mph".
The prosecutor can't have it both ways: either we were all speeding or we were all within the limit.

2) The bike's 'passenger' was an observant pillion: she was able to give detailed answers to questions about speeds, about distances and about locations.
This may be considered surprising because pillions often have a poor view of the road ahead, particularly if they sit lower than the rider.
The driver / rider said his pillion sat slightly lower than him.
However, the pillion said she sat slightly higher and could look round him.
Whichever was true, passengers, whether on motorcycles or in cars, don't usually pay much attention to speeds, distances and other driving matters. Why would they?  Accordingly, they are likely to find such details difficult to recall.
The pillion managed it (mostly): she had evidently been well-coached.

3) The 'witnesses' were able to identify me through the car's windscreen. Nobody in court thought there was any difficulty about this.
Reader, you will know it ain't easy: reflections on the glass often make it impossible even to see a person through a windscreen, let alone identify them.

4) Carnegie told the Fiscal Depute he'd written down the bike’s registration number on the same piece of paper he had earlier used to record my car’s number.
But he told the Sheriff he'd recorded both numbers at the same time, at the Strathmartine Road roundabout.
Nobody asked how, as a confused and traumatised driver, he'd managed to do this whilst driving at speed along the Kingsway.

5) Carnegie claimed he recorded the bike’s registration number, but never said why. The court must have presumed it was because he thought the riders would be willing witnesses. But no one in the court asked why he thought this.

6) Having been on the receiving end of a piece of dangerous driving and then 'witnessing' the same reckless driver cause a near accident, the Sheriff might have wondered why the motorcyclists did not themselves report the driver to the police.
But the question was never asked.

How did they do it?

This is my take on what really happened that evening:

The biker, as he accelerated away from the Myrekirk Road roundabout, had a clear view of the road ahead (there was no traffic in the way).
About 400 metres ahead he could see a dropside Transit and a couple of cars, one of which, in the outside lane, had its brake lights on.
In no time at all he'd caught up and recognised the braking car as his friend's Astra. He realised that Carnegie had been held up by a blue Citroen that was now back in the inside lane.
The pair had played this game before - racing along the Kingsway, intimidating any motorist who got in the way of their fun.
So he slowed down just ahead of the Citroen, twisted round in the saddle to glare at the driver, then pointed with his gloved left forefinger at his friend's car.
Then he sped off, heading for his home near Carnoustie.
Later that evening, he would receive a call from his friend asking him to act as a witness to a certain road traffic incident.

Carnegie left the dual carriageway, probably at the Macalpine Road junction (though he said it was at Strathmartine Road), where he stopped at the adjacent Retail Park (he told the court he was going shopping) to consider his next move.
He then went to the Balgowan Avenue Police Office (2.5km away on the other side of the Kingsway) to fake his complaint. There is no information on how he did this: he may have spoken to an officer or he may used the station's phone.
Afterwards, he drove home to 29 Dalgetty Court, Muirhead to await the arrival of the investigating officer.

Constable Kenneth Bell, of the Forfar Police Office, was instructed to proceed to Carnegie's address in Muirhead shortly after 6pm and arrived at 7pm.
Forfar is in Tayside Police's Eastern Division, while Muirhead is in its Central Division.
Quite why a provincial policeman was asked to make a 30 mile round trip to a different division to attend a minor complaint is an interesting question.
But one that was never asked, because my complacent solicitor did not require Bell to attend court.
I discovered that the Training Officer at Forfar, PC Philip Gill, happens to be the stepfather of Carnegie's daughter Craigie.
I concluded that PC Bell probably knew, or at least knew of, the man he was told to interview in Muirhead that evening.
The full significance of this piece of knowledge is unclear: it would at least have offered Carnegie scope for obtaining inside information on police and court procedures. Perhaps Carnegie was calling in a favour from friends at Forfar Police Office.
Or it could have been an elaborate conspiracy aimed at defrauding insurance companies; if so, Carnegie would have been disappointed when PC Bell presented his findings:
Bell reported that he examined Carnegie's Astra and "found a slight scuff mark on the front offside tyre".
No measurements were included in his report. Despite Carnegie's claim that his wheel had been damaged when his car hit the central reservation, Bell did not speculate on the cause of the alleged damage. He didn't work in Dundee, so might have been unaware that it could not have been caused by the kerb, because the kerb is bevelled, allowing wheels to ride harmlessly over it. If he had known, he might have told Carnegie to stop wasting police time.
But he didn't: Carnegie gave him the registration number of his so-called witness's motorbike and Bell later took statements from him and his girlfriend.
Although Bell did not say when or where he obtained them, Moir, the biker, said in court that it was "a day or two later", at his home.

The broken-down van
There was no mention of the broken-down van in any of the statements given to PC Bell.
The Procurator Fiscal's office refused to tell me exactly when they learned of it.
It seems to have been added to the 'evidence' as an afterthought and the source of the information is a mystery.
At first I thought it might have come from Carnegie's police contacts.
Then I wondered if he had learned about it while monitoring police radio traffic - he is a radio ham, though mostly FM.
However, I now consider it likely to have come from the 'pillion', MacGregor .
She must have left work in Perth up to 45 minutes after her boyfriend and, getting caught up in a traffic jam at the Swallow roundabout at around 6pm, would have noted the cause: a vehicle, a white van, stranded by the side of the road, perhaps with a breakdown vehicle and a police patrol car in attendance.
It is odd that she made no mention of the broken-down van in her Precognition Statement given in late January 2005.
It could be that when the conspirators realised, after the Intermediate Diet of 16 February, that I was continuing to plead Not Guilty, they decided to bolster their case with some additional 'evidence'.
So they would have programmed their Improbability Drive to take the broken-down van back in time and teleport it a mile up the road, telling the Fiscal Depute it was the cause of the Accused's swerve into the path of the Astra.
It would have helped to make their tall tale more convincing.