When Clair Allison received a court summons for speeding, she was determined not to take it lying down.
Ms Allison was determined to win her case
The 46-year-old single mother-of-one started a campaign that ended in the overturning of thousands of fines - together with some red faces among speed camera bosses.
And, in a further twist, it was her £5 disposable camera which helped dismantle a prosecution that relied on the latest sophisticated photographic equipment.
Ms Allison was snapped on the A303 at Folly Bottom, Wiltshire, at temporary roadworks in December 2003.
She had been travelling from her home in nearby Amesbury to work as a make-up artist at Sky News in London.
It was a road she knew well, with a 70mph speed limit.
She recalls: "No one was working and the road was clear. There were no speed signs up and I just drove through. Two weeks later I got a court summons.
"They said they clocked me at 75mph [in a 40mph zone]."
After hearing about a speeding case on Radio 4's You and Yours, she contacted solicitors and brushed up on her knowledge of the law.
Armed with the throwaway camera, Ms Allison began taking shots of the roadworks.
Realising that hundreds of other drivers may also have been zapped, she placed petitions in garages and post offices to find fellow defendants.
In February this year, she challenged the speeding prosecution and saw it dismissed because of a lack of evidence from the Crown Prosecution Service (CPS).
Ms Allison said: "My pictures were their evidence. If I had caved in, everyone would have gone down."
More than 4,200 people were fined after being caught between October 2003 and August 2004, according to the Wiltshire & Swindon Speed Camera Partnership.
But Ms Allison's solicitor says this figure could be as high as 6,200.
Following a CPS review, they will all now have their fines overturned and their penalty points removed - to the delight of Ms Allison.
"I have had some lovely calls from elderly people saying they have got their money back.
"Lots of people were embarrassed - they had never had problems like this before, and felt shameful," she added.
The case may also have left the safety partnership having to refund at least £250,000 in fines.
The police have said that each case could cost up to £250 to review - and there are court costs and compensation claims to consider.
The camera partnership is, however, sticking to its guns.
Spokeswoman Saira Khan said: "The speeding offences are proven - it is the signage that isn't."
But she admits the organisation needs to enforce speed restrictions properly to keep the public on side, and is working with the Highways Agency on checking regulations.
Who is to blame?
The agency is keen to see that lessons have been learned.
Spokesman Robin Millar said: "We wrote to our contractors reminding them of the importance of the procedures."
But Ms Allison is not satisfied and wants to know who is to blame.
She has met senior officers at Wiltshire Police and plans to take matters further with the Independent Police Complaints Commission.
"We have still not got to the bottom of this, she said. "Everyone blames each other."