During Tuesday's hearing on the safety of natural gas infrastructure in Massachusetts, a key lawmaker questioned whether the consulting firm the Baker administration brought on to evaluate the state's gas system is truly independent of the gas industry and whether its report will be free of bias.

In the wake of the natural gas disaster in the Merrimack Valley, Gov. Charlie Baker's administration contracted with Canadian company Dynamic Risk Assessment Systems Inc. to examine and make recommendations about "the physical integrity and safety of the natural gas distribution system and the operation and maintenance policies and practices of all natural gas distribution companies operating within the Commonwealth."

During a hearing on gas safety Tuesday, Joint Committee on Telecommunications, Utilities and Energy co-Chair Sen. Michael Barrett said he is concerned with the selection of Dynamic Risk to conduct the infrastructure review because the company appears "to be part and parcel of the industry." Administration officials insisted they will hold the firm accountable for its work.

Barrett pointed to a "proud boast" on the Dynamic Risk website in which the company touts that "operators of 42 percent of the pipeline mileage in the USA and 75 percent of operators in Canada count on Dynamic Risk" as an indication that the firm relies upon the continued operation of gas utility companies for its own future.

"It's good that they count on Dynamic Risk and I am not immediately questioning the integrity of its work, but I do question at this point how free Dynamic Risk Assessment Systems is to be a critic of the industry," Barrett said.

The chairman asked executives from five of the state's gas utilities -- Columbia Gas, Eversource, Berkshire Gas, National Grid and Unitil -- whether any of their companies had done work with Dynamic Risk. All five said they were not aware of any prior connection to the Canadian company which has an American office in Texas.

"That's reassuring," the chairman said. "They do seem to be very close to the industry but it is good -- and I really mean this -- that you haven't done work with them in particular."

Later during Tuesday's hearing, Secretary of Energy and Environmental Affairs Matt Beaton defended the selection of Dynamic Risk.

"We did, quite honestly, a nationwide search -- an international search given it being a Candian company -- for the best company that had both the technical expertise which is critical in an exercise like this but did not have any local bias having worked ... with any of the local utilities," Beaton said. "At the end of that process and the vetting process, it was a unanimous decision that this company be brought forward as the company to do this exercise based on those criteria."

Beaton said that the work Dynamic Risk was contracted to perform is the "phase one" of the project and told Barrett that his office will "hold their performance against them" as the second phase of the project gets underway.

The secretary told lawmakers that he and the Department of Public Utilities will "most certainly hold them very accountable and we will expose them to every side of criticism."

Barrett asked if Beaton would commit to having representatives of Dynamic Risk appear before his committee before the firm completes the first phase of its work, and Beaton suggested that he would support such a request.

"I would want to consult with some folks on my team on that before committing, but that is most certainly something I think we would push for and consider," Beaton said. "Barring any conflicts or anything that might get in the way of that, I most certainly will encourage that and make sure we see that happen."

Through authority granted under the state of emergency Baker declared immediately after the Merrimack Valley gas fires and explosions, the DPU is requiring that the state's gas companies pay the costs of the infrastructure review.

A preliminary report is due by February or early March, according to the timetable announced by the Executive Office of Energy and Environmental Affairs.