But suspicions were raised when his supervisor noted he was difficult to get in touch with towards the end of the day.
Manager Mike O'Donnell checked Stuart's work truck GPS log, which recorded the time and address of every start and stop, the distance between stops, the idling time and the average speed of each journey.
He found there was often a mismatch between the time of the truck's last stop at Stuart's house and the finish time on his timesheets. When Stuart was called in for a disciplinary meeting in December 2010, he admitted taking longer lunch breaks than his half-hour allowance. He explained that over two weeks the previous month, he had stayed at home to watch the Pike River disaster.
Stuart also explained that some of his time was spent preparing for the afternoon shift by cleaning his truck or maintaining his equipment. He offered to make up the extra time on the weekend, but his employers declined.
Downer found Stuart had been systematically falsifying his job records and dismissed him for serious misconduct.
Stuart filed a personal grievance claim, seeking $12,000 in compensation for unjustified dismissal.
He said the decision to sack him was overly harsh, given his 6 years of service without any complaints. He also claimed the decision was predetermined, citing the "smug grin" on O'Donnell's face as evidence.
ERA member David Appleton found Downer was justified in dismissing Stuart.
An analysis of his job records showed he claimed a total of 17 hours in excess of his lunch allowance, as well as almost 46 hours at home at the end of the day, between June and December 2010.
The ERA dismissed Stuart's claim for compensation and dismissed Downer's counterclaim to get back the extra pay.
Big bro is watching
Unite union president Gerard Hehir says workers should be aware technology has allowed bosses to "monitor, control and intrude" more than ever before.
* Video cameras watched live by managers
* GPS tracking through mobile phones
* Keystroke monitoring of computers
* Measuring time not spent on the phone, in some call centres
* Automatic monitoring of emails with key words
* GPS tracking in work cars, to monitor speed and location
* Reading text messages and work emails remotely
* Facebook and webmail pages that the computer keeps
"If the company owns the piece of equipment, it is theirs to look through," Hehir says.