After years of criticism from lawmakers and auditors, Capitol Police officials are changing the way they handle the department’s finances.

Last week, Chief Phillip Morse gave Congress a rundown of those changes, which include detailed analysis of police staffing needs and a top-to-bottom review of the department’s finances.

It’s partly an effort to gain back the confidence of Congressional appropriators, who in past years have expressed concern over how the department spent its money. On Thursday, Rep. Mike Capuano (D-Mass.) reiterated this concern at the first-ever hearing of the House Administration Subcommittee on Capitol Security.

“It makes it difficult to do our side when we can’t trust the numbers,” said Capuano, who recently took over as subcommittee chairman.

As the hearing progressed, however, Morse and a Government Accountability Office analyst laid out the substantial changes already made to the department’s once-lagging financial arm.

Over the years, the GAO has criticized the finances of the Capitol Police in several reports — and for awhile, not much was done. But in the past 15 months, the Capitol Police has implemented about a third of the GAO recommendations made since 2004.

One landmark was the completion of the department’s first-ever full set of financial statements, which include an inventory and an assessment of everything the Capitol Police owns. Before those statements, the department was never able to say exactly what it was worth — and was consequently unable to map out when it would need to replace equipment.

“It’s just like a corporation, and it is really a standard business practice in any corporation in the private industry,” Morse said in an interview. “You eliminate any waste, any fraud, any abuse, and you facilitate good management practices to be the most efficient.”

During the past year, officials have also surveyed every one of the hundreds of police posts on the Capitol campus, which is an “enormous undertaking,” Assistant Chief Daniel Nichols said. For each building and each post, Nichols and his team determined the specific threat, the physical layout and the volume of people, among other things.

When finished, they will have a binder that details exactly how many officers they need at each post and why that number is necessary. Now, lawmakers will see the purpose of each officer, he said, and ongoing surveys will “allow us to be more dynamic.”

But it will take time. If the department needs new officers, it can’t find them instantly. Training takes time, and other costs — such as equipment and administrative support — need to be considered, Nichols said.

Even now, the department has almost 100 fewer officers than it is entitled to have. On the administrative side, 31 positions remain vacant.

House Sergeant-at-Arms Bill Livingood said he was proud of the department’s progress, especially in the face of the immense growth of responsibilities and personnel since Sept. 11, 2001.

In the past decade, the department has added hundreds of officers, reaching 1,600 this year.

Now the department is “getting the right people” for the administrative side, Livingood said. Indeed, the new chief administrative officer, Gloria Jarmon, comes straight from a job at the GAO.

But Nichols said it was hard to fill the administrative slots. Such a high number of vacancies puts an increased workload on those already working, he said, and that causes some to leave. But Nichols and Morse said filling those slots is a top priority.

The goal is to make the department more “business-based,” Nichols said.

“The goal is to be the right size and to be able to deliver the right performance,” he said.