FOLLOWING THROUGH on a contentious campaign promise, state Auditor Diana DiZoglio announced Tuesday that she intends to audit the Legislature, an institution she served in for more than a decade as an employee, state representative, and state senator.

“We hope this will increase transparency, accountability and equity in an area of state government that has been completely ignored,” DiZoglio said in a statement. “Historically, the Legislature has been a closed-door operation, where committee votes have been hidden from the general public, and legislation has been voted on in the dark of night.”

This would be the first audit of the lawmaking body since 1922, DiZoglio’s office said, calling out Massachusetts’ reputation as “one of the least transparent and least accessible state governments in the nation.”

DiZoglio pledged on the campaign trail that, along with the shambling MBTA, the state Legislature would be in her sightline. In promising the legislative audit, DiZoglio said during her campaign that she was particularly interested in the use of non-disclosure agreements on Beacon Hill.

When DiZoglio was an aide on Beacon Hill in 2011, she says her then-boss fired her because of unfounded rumors of impropriety. Though the speaker’s office determined it was a wrongful termination, DiZoglio said she felt pressured to sign a non-disclosure agreement to get severance. She successfully ran the next year for a state representative seat and later broke the NDA by speaking out publicly about her treatment.

“I did this to make sure others would not be forced into silence like I had been as legislative staffer who experienced sexual harassment on Beacon Hill,” she wrote in a CommonWealth op-ed last April.

That transparency pledge was front and center in her campaign for state auditor.

“Sunlight is the best disinfectant,” she wrote in the op-ed. “It is my hope that the Legislature will welcome the opportunity for an audit to shine a light on where we can, and must, do better. If compliance with an audit is refused, however, then the fight for transparency would simply need to be taken to court.”

Responding to DiZoglio’s proposal at the time, then-Auditor Suzanne Bump said the office did not have the power to audit the Legislature. In a statement, Bump said the enabling statute of the auditor’s office grants her the authority to audit more than 200 executive branch agencies.

“The Legislature is not among that list; therefore, the Office of the State Auditor by law does not have the authority, express or implied, to audit the Legislature,” the statement said. “Moreover, the Legislature is not an agency or department but rather another branch of government and, thus, subject to protections under the separation of powers doctrine. Just as the Office of the State Auditor looks to its auditees for compliance with their statutes and regulations, the Office of State Auditor too is bound by the limitations of its enabling statute and must act within its prescribed authority.”

Bump said prior to taking office she had also planned to audit the Legislature. “I quickly learned otherwise,” Bump said in an episode of The Codcast reflecting on her time in office.

Throughout the campaign, DiZoglio said she was confident that the office did, in fact, have oversight powers.

State Auditor Diana DiZoglio

“[N]owhere in the statute laying out the powers of the office is the auditor prohibited from investigating the Legislature,” she wrote. Where the legislature decides it is exempted from oversight, such as public records requests, it details the exemption specifically, DiZoglio said. “It has not done so here.”

DiZoglio’s office informed the Legislature of the pending audit on Tuesday afternoon, just hours after the auditor testified before her former colleagues on her proposed budget for the coming fiscal year.

Though no specific targets were set out in DiZoglio’s statement, letters sent to the House of Representatives and the Senate laid out a broad mandate.

According to the letters, the audit “will include but not be limited to the review of access to budgetary, hiring, spending and procurement information, as well as information regarding active and pending legislation, the process for appointing committees, the adoption and suspension of House and Senate rules and the policies and procedures of the House and Senate.”

DiZoglio’s office expects to schedule a formal meeting with representatives from the Legislature to discuss the audit this month.

In a comment Tuesday evening, a representative for Senate President Karen Spilka suggested that the chamber was already subject to public scrutiny.

“Under the Massachusetts Constitution and as the separation of powers clause dictates, the Senate is required to manage its own business and set its own rules. Those rules require that the Senate undergoes an audit every fiscal year by a certified public accounting firm experienced in auditing governmental entities and provide that audit to the public,” the spokesperson said in a statement. “Further, Senate business is made public through journals, calendars and recordings of each session, while payroll and other financial information is publicly available on the Comptroller’s website. If anyone wishes to view this information, it is available to the public.”

A spokesperson for House Speaker Ron Mariano declined to comment immediately.

The announcement of an audit of the Legislature follows close on the heels of similar announcements in regard to safety at the MBTA and the Boston Exhibition and Convention Center. DiZoglio similarly had promised to do an audit of the MBTA on the campaign trail, but she said after the budget hearing that the T and convention center audits were being done as part of her office’s responsibility to audit some 209 government entities every three years.

At the budget hearing, DiZoglio said the office for many years has not been able to comply with the requirement to audit the government entities every three years. To accomplish that task, she said, her office would need 49 additional audit staffers at an estimated cost of $2.6 million.

The other option, she said, would be to spread the audits out over four years, which require the addition of 23 employees at a cost of $1.22 million.Gov. Maura Healey’s budget, DiZoglio said, recommends the four-year cycle.