Union leader Gail Cartmail has called for a criminal investigation into the collapse of Carillion.
Speaking at the Trade Union Congress in Manchester, Ms Cartmail, who is Unite’s assistant general secretary, called on delegates to push for an immediate investigation into the individuals connected to the contractor’s demise.
“There must be an immediate criminal investigation into Carillion,” she said
“If no laws were broken, then we need, better, stronger laws.”
Ms Cartmail also attacked the length of time taken by the Insolvency Service to investigate the failed firm’s bosses.
The Insolvency Service revealed last month that its investigation into the cause of the contractor’s failure and the conduct of its directors was “under way”.
Business secretary Greg Clarke fast-tracked the Insolvency Service probe in the aftermath of the firm’s liquidation with the minister also broadening the scope of the investigation.
Mr Clark said at the time he was asking the Insolvency Service to examine “not only the conduct of the directors at the point of its insolvency, but also of any individuals who were previously directors”.
“Any evidence of misconduct will be taken very seriously,” he added.
There are currently two other open investigations into Carillion’s liquidation.
The Financial Reporting Council is looking into the conduct of former finance directors Richard Adam and Zafar Khan alongside the financial audits carried out by KPMG between 2014 and 2017.
In May, the FRC said its lawyers and accountants were making “good progress”, and that it would not “cut corners” to speed up the investigation.
The Financial Conduct Authority (FCA), which is examining allegations of market-based infringements, revealed in June they were considering “allegations of insider trading” as part of its investigation.
A spokesperson for the Official Receiver said: “We began investigating the conduct of Carillion’s directors immediately following the company’s liquidation in January.
“This is a complex investigation covering 326 linked companies and any findings of misconduct will need to be supported by sufficient evidence to convince a judge to make a disqualification ruling.
“In parallel to this investigation we have successfully transferred all of Carillion’s contracts to new suppliers, saving over 13,000 jobs and ensuring vital public services continued to be delivered uninterrupted.”