Field sent HMRC information last month, which he claimed was evidence of the courier failing to meet minimum wage requirements for its self-employed couriers.
Responding to Field in a letter dated 10 October, HMRC executive chairman Edward Troup said that “individuals cannot be opted out of employment rights and protections simply by calling them self-employed”, and added that the body was “committed to tackling false self-employment”.
He added that he had sent Field’s information to compliance teams “for consideration”, and that if it found a company had “misclassified” people as self-employed, it would take “all the necessary steps” to make sure that they pay the appropriate tax and penalties.
HMRC declined to comment further on the Hermes investigation to Motortransport.co.uk, but said that it has created a specialist unit - the Employment Status and Intermediary Team - to crack down on on companies using "false" self-employment.
Financial secretary to the Treasury Jane Ellison also responded to Field earlier this month in her capacity as minister in charge of the policy area, stating that the government is "committed to taking strong action" against companies using this method to reduce costs at the expense of workers' employment rights and benefits.
In response to the latest development, a spokeswoman for Hermes said: “Hermes employment practices were reviewed by HMRC in 2011 and we remain confident that our service agreements with couriers are legitimate self-employment.
"We will fully comply with any investigation should there be one.”
After the Guardian published its initial investigation into Hermes' use of self-employed couriers, the company's chief executive Carole Woodhead told Motortransport.co.uk that in some instances, it had not been “as compassionate as it expected itself to be”.
However, she added that it had introduced measures to combat this, including a new code of conduct, an internal panel for complaints from couriers and an external ombudsmen as a final recourse if people are still dissatisfied with their treatment.
Woodhead said: “We have committed to being bound by any decision it makes about a case, which I think is part of giving confidence externally that our standards are good and that we treat people fairly.”