HONG KONG — An independent committee investigating the cause of Hong Kong’s deadliest fire in decades heard arguments on how improper practices that evaded regulatory oversight turned a small fire into a tragedy as the case neared its conclusion Friday.

The November blaze spread through seven buildings of an apartment complex, killing 168 people and displacing thousands of residents at Wang Fuk Court in the suburban Tai Po district. Many of the residents now live in temporary housing.

Committee lead lawyer Victor Dawes said the use of non-fire-retardant scaffolding netting was very likely a key reason for the fire’s rapid spread at the complex, which was undergoing a major renovation project when the blaze started. Having wooden planks boarding up staircase windows caused plumes of smoke in residents’ escape routes, he said.

He said Will Power Architects Company, a consultancy, and Prestige Construction & Engineering Co., the main contractor on the project, cut corners in the work and the materials, in addition to deceiving regulators and homeowners, he said. Various substandard and improper practices were involved, including faked compliance of inspections. Certain professionals responsible for inspections signed documents like a “rubber stamp,” he said.

Dawes also criticized the government’s reliance on an honor system in overseeing the project, saying relevant departments should bear responsibility.

“When faced with dishonest bad actors, the entire system collapsed,” he said.

Several residents wept during the hearing that was concluded Friday.

On Thursday, Lawyer Jenkin Suen, representing the government, acknowledged some systemic vulnerabilities but said it would be unfair to say government departments were the instigators of the fire. Some professionals and contractors abused a mechanism that aimed to protect the public and betrayed the trust placed in them, he said.

Jeffrey Tam, a lawyer for nine residents of the Wang Fuk Court, noted some residents decided to give evidence despite being distressed by the tragedy.

“But we heard some witnesses appear that they just wanted to to be shirking responsibility,” he said. “So sometimes I also understand why they could not hold back their anger.”

He added deflecting responsibility like this would not help the city find out the truth.

The investigating committee led by High Court judge David Lok is expected to give recommendations after reviewing the fire’s cause, potential systemic problems and whether existing regulations and penalties are sufficient. When the committee’s findings will be released is not known.

But its scope of work does not include possible legal liabilities, which will be handled by law enforcement authorities.

Last month, Hong Kong authorities charged seven people and two companies in June with offenses including manslaughter and conspiracy to defraud over the fire. The companies include Will Power and Prestige Construction & Engineering Co.