Dapto man Anthony John McCabe, the owner of McCabe Transport, pleaded guilty in a Sydney court on Tuesday to 81 charges relating to his company's repeat breaches of driver safety laws.

McCabe, as director of the company, was also held responsible for the breaches, and pleaded guilty to a further 78 charges.

The 159 offences relate to McCabe Transport drivers falsifying time diaries, including recording of their work and rest hours, in November 2011 and October 2012.

The discrepancies were discovered when the driver's log books were compared to other business items such as fuel receipts, toll statements and loading and unloading records at various pick up and delivery sites.

The court heard McCabe was responsible for preparing the schedules for his drivers, who travelled throughout New South Wales, South Australia and Victoria transporting goods.

In an agreed statement of facts, McCabe admitted those schedules were often impossible to meet, and drivers would miss deadlines if they did not drive longer than was legally allowed in a 24-hour period.

"It was Mr McCabe who was allocating the work and demanding it be done," Roads and Maritime Services lawyer Gabrielle Bashir, SC, said.

In one such case, a female employee recorded in her work diary that she had stopped for a rest at Broken Hill between 3pm and 8pm while on a long haul trip between Sydney and Port Pirie in South Australia.

However a fuel receipt showed she filled up with diesel at Dubbo - some seven hours from Broken Hill - at 3.28pm.

Prosecutors claim the discrepancy, backed up by other evidence, demonstrates the woman was driving between 3pm and 8pm in order to get to Broken Hill in line with her schedule.

The following day the woman recorded 15.5 hours of driving on her way to Port Pirie - well above the 12-hour limit allowed per 24 hours.

The day after that she did not record any driving time in her work diary, despite fuel records and time sheets from the company showing she drove from South Australia to Melbourne.

That employee was later sacked after advising McCabe one day that she was no longer going to disobey the heavy vehicle laws, with McCabe telling her he "didn't think interstate driving was for her", the court was told.

Ms Bashir said another employee' fudged log book was picked up after records showed his truck passing through toll points in Sydney when he claimed he wasn't working at all that day.

She submitted the type of offences and the sheer number demonstrated there was a "culture of non compliance [at the company] which at the very least was tolerated".

McCabe's lawyer, Stephen Coleman, said his client had had a system in place to check driver's log books for discrepancies, however admitted it clearly wasn't adequate, conceding there was no cross checking of the books with items such as fuel receipts or toll accounts.

The sentencing hearing will continue on Wednesday.