The six-storey building was destroyed in February 22, 2011, quake, killing 115 people.
The Engineering New Zealand disciplinary tribunal is expected to sit for three days to determine if Dr Alan Reay properly supervised engineer David Harding who designed the CTV building in 1986 when he worked for Alan Reay Consulting Engineers.
The Press reported Reay's lawyer, Willie Palmer, issued a media statement on his behalf, which was embargoed until 9am when the hearing started.
The statement said the 82-year-old, who is retired, was medically unfit to attend the hearing, The Press reported.
Reay's legal team said the hearing was limited to determining whether his supervision of employee David Harding was adequate.
The complaint focused on employment procedures in the mid-1980s, a time when standard employment practices, including the degree of supervision of employed senior engineers, differed markedly from that of today, counsel said.
The Ministry of Business, Innovation and Employment claimed Dr Alan Reay breached his professional obligations, based on Royal Commission findings that the design was seriously deficient.
An Engineering New Zealand committee will examine whether Reay failed to adequately supervise an inexperienced employee who designed the building and, if so, what action should be taken during a disciplinary hearing in Christchurch on Monday.
The 82-year-old, who is retired, lost a protracted fight to stop the hearing, culminating in a High Court bid.
The 2012 Canterbury Earthquake Royal Commission found engineer David Harding made fundamental errors in designing the CTV building back in the late 1980s and criticised Reay for handing sole responsibility for the design to the inexperienced employee.
The same year, the ministry's chief engineer and 54 family members made complaints about both men to an industry professional body, saying Reay knew Harding did not have the necessary experience to design this type of building and failed to adequately supervise him.
Reay was a member of the Institution of Professional Engineers New Zealand at the time, which is now known as Engineering New Zealand.
Engineering New Zealand wanted to pursue a disciplinary hearing to decide whether or not there are grounds to disciplining Reay and how to do so, while the 82-year-old wanted the process to be abandoned because of how much time has passed and questions over which rule he was said to have broken.
But the following year a rule change meant a disciplinary process could still go ahead, even if a member had resigned.
Since then, there have been years of litigation including appeals and High Court decisions about whether disciplinary action could be taken, as well as a separate police investigation which did not result in any criminal prosecution for the building's collapse.
It all came to a head in October, when a High Court judge ruled in favour of a disciplinary hearing.
The disciplinary committee hearing is essentially an inquiry, not a court hearing, so Engineering NZ can ask for people to appear but it cannot compel them.
The committee will decide whether there are indeed grounds for disciplining Reay, and if so, whether it can impose any penalties.
At October's High Court hearing, his lawyer argued there was not an explicit requirement in the 1980s for him to supervise his employee, and said there was no need to protect the public because he had now retired.
But the victims' families have said they wanted people to learn from what went wrong so it did not happen again.
The hearing is expected to run for at least two days.
