BOSTON -- A key state senator called for continued scrutiny on the Registry of Motor Vehicles as the Baker administration addresses a years-long failure to suspend licenses, reiterating skepticism over whether the governor knew about the problems before a fatal crash brought them to light.

Sen. Eric Lesser, the second-ranking Senate member of the Joint Committee on Transportation, told WCVB that the committee is planning further hearings to seek answers to "a lot more questions," even after grilling RMV and administration officials for more than seven hours in July about how the department allowed thousands of driver violation warnings from other states to pile up unprocessed.

Two key RMV employees have departed in the wake of a fatal crash allegedly caused by a driver whose license should have been suspended: former Registrar Erin Deveney, who resigned days after the June 21 crash, and Merit Rating Board Director Thomas Bowes, who told lawmakers his short-handed department chose not to process out-of-state notices and was fired two weeks ago by a long-inactive board of the same name.

Lesser, who called for Bowes to leave his position one day after the director testified at the oversight hearing, said Sunday that he "had to go" but that the administration's response should not end there.

"The worst thing that could happen is those two people go and then the Department of Transportation says, 'we're done here,'" Lesser told WCVB in an interview that aired Sunday. "That's very dangerous, and I think the Legislature needs to stay on top of this, and they are."

Like other committee members and House Speaker Robert DeLeo, Lesser implied in his interview that he is still not convinced by Baker's claims that he was unaware the RMV was not processing key warnings from other states for years.

Baker told reporters in July that he only learned of the problem on June 25, the day that Deveney resigned, and Pollack said in her testimony before the committee that the RMV had an "institutional belief that this was not a serious safety problem."

Asked if Baker's confidence in Pollack is well-placed amid the RMV scandal and frequent disruptions on the MBTA, Lesser replied that "the question is still out."

"One of the things I'm particularly interested in finding out is: what did the governor know, and when did he know it, about the issues at the RMV, about the, frankly, gross mismanagement?" Lesser said during the interview. "Was there, for example, an overemphasis on the customer-facing elements of the RMV, reducing the wait times -- which were worthy goals that the Legislature supported -- but in focusing on those customer-oriented elements, did they take their eye off the ball in the back-end safety issues?"

"Those are the important questions we don't have the full answers to yet," Lesser continued.

A Baker spokeswoman on Tuesday referred to Baker's previous statement about when he learned of the RMV woes.

Lesser said in the WCVB interview that his focus is on "passing laws and making changes to make sure this doesn't happen again." His spokesman said Tuesday that it's unclear at this point what specific legislation the senator wants lawmakers to pursue in the wake of the scandal beyond a bill Baker filed (H 3980) in July to strengthen restrictions on commercial drivers. That bill is currently sitting before the Joint Committee on Transportation awaiting a hearing.

As detailed in status reports from Acting Registrar Jamey Tesler, the RMV worked through the backlog of tens of thousands of notifications following the crash and suspended licenses of more than 2,400 Massachusetts drivers.

In New Hampshire, where the Zhukovskyy crash occurred, Gov. Chris Sununu announced last week that his state's Department of Motor Vehicles suspended licenses of more than 900 drivers from its own backlog of unprocessed paper out-of-state notifications dating back to September 2017.

That backlog of about 13,000 notices has since been cleared, New Hampshire officials said last week, and no fatalities were associated with the new licenses suspended.

Sununu argued that the problems in New Hampshire were not directly comparable to those in Massachusetts, though, describing the two backlogs as "night and day." New Hampshire, he said, did have thousands of out-of-state notifications unprocessed for years, but the backlog was being targeted regularly if slowly.

In Massachusetts, the Merit Rating Board had virtually stopped handling the paper notices in March 2018, and thousands were later found tucked into mail bins in a storage room.

"There was massive systematic failure within the state of Massachusetts," Sununu said at the press conference. "It is so big, so widespread, you have issues of boxes not being found and in the closet and all of that kind of stuff — that was not the issue here. All of these workflows, while there were backlogs, were constantly being addressed while the system was going through a transition, so it's really an apples and oranges comparison."

Baker ordered national audit firm Grant Thornton to conduct an independent investigation as well. A preliminary report last month revealed that one RMV employee viewed the digital alert from Connecticut about Volodymyr Zhukovskyy, the West Springfield driver who allegedly killed seven motorcyclists in a crash, for seven seconds but did not act on it because he was not trained to do so.

While Lesser said the audit has uncovered valuable information, he stressed that he and his colleagues must continue their parallel inquiry. Lesser referenced the committee chairs' requests for internal RMV documents, some of which — although the Department of Transportation says it has provided more than 500,000 pages of material — remain unfulfilled.

"I think that audit is a good first step, but let's keep in mind the auditors work for MassDOT," Lesser said. "They were commissioned internally by MassDOT to look at their own house. We need a separate branch of government, the Legislature, to be taking a look at this."