Serious concerns about the safety of Nexus staff were raised repeatedly years before an employee was electrocuted while working on the Metro line, a court has heard.
John Bell died in July 2014 while carrying out maintenance work on overhead cables near the Tyne and Wear Metro Operator's depot in Gosforth, Newcastle.
The 43-year-old, from Killingworth, North Tyneside, was electrocuted after grabbing a wire he believed to be isolated from the power supply, but was in fact live.
An inquest jury returned a verdict of accidental death in 2018.
But Nexus has since pleaded guilty to a charge of breaching general duty to an employee.
The company is now facing a fine that could run into six figures.
As a sentencing hearing got under way on Monday, Newcastle Crown Court heard how serious concerns about poor safety procedures were raised on numerous occasions before the tragedy.
Judge Robert Spragg was told how a technical manager was so worried about the work of production supervisor Ian Willis, who was responsible for safety, that he began keeping a log of his concerns as early as 2009.
And in one email to engineering manager John Henderson, the technical manager described what was going on as: "Dangerous, very, very dangerous."
Gordon Menzies, prosecuting, explained how Mr Willis' role put him in charge of supervising and training staff, and ensuring work was carried out safely on the lines.
But he gave examples of a number of incidents in which correct procedures were not followed.
These included 'method statements' not being produced for work.
Mr Menzies said that vital safety procedures were viewed more as administrative tasks.
"This paperwork is there for safety purposes," he explained.
"The approach taken was to treat paperwork as administration, rather than safety critical."
Mr Menzies said Nexus was aware of the shortfalls, and that the technical manager had raised his concerned with the company's HR department in 2012.
"It was a state of affairs that arose and continued for a long period of time. It was known by Nexus," he said.
"Whether you call it casual, complacent or lax, there was a problem with health and safety standards.
"The prosecution's case is that Nexus could have done something about it."
The court was told how Mr Bell, who had worked for Nexus for 16 years, died while carrying out planned works, on July 6, 2014.
Mr Menzies said sufficient checks were not carried out to test the lines were safe to work on, after insulators were installed to cut power to the specific cables.
He said had these tests been carried out the live wire that killed Mr Bell could have been discovered.
And that no 'permit' confirming safety to work was produced.
"One of the fundamental parts of the commissioning process was to test if what had been done was working," he said.
"Perhaps the most tragic aspect of it was that Mr Bell himself raised the issue of lack of permit to work himself, and Mr Willis said it could be dealt with later.
"This perhaps demonstrates the dangers of viewing such safety critical procedures as administration."
The hearing continues tomorrow.
