On the surface, at least, the system operated as designed.  

A member of the public went exactly where he’s supposed to get inside the halls of Congress.  

That’s the main entrance to the Capitol Visitor Center, an underground lobby at least 250 steps away from where any lawmaker has an office.  

There he was confronted by a long row of metal detectors, augmented by the sort of full-body scanners now ubiquitous at airports, along with a phalanx of Capitol Police officers acting as both greeters and keen observers of anything out of the ordinary.  

And when the moment suddenly turned violent, thousands of people who work for the legislative branch knew precisely what to do when they were ordered to shelter in place during the next hour of anxiety and uncertainty.  

In fact, many had been drilled for just such a lockdown scenario just a few hours before – a rite of passage during congressional recess periods (this week is one) in the years since the Sept. 11 attacks.  

“It appears the screening process worked the way it’s supposed to,” Capitol Police Chief Matthew Verderosa said after the all-clear was announced Monday afternoon, reminding reporters that more than 2 million people now use the CVC entrances annually. “People can safely visit the United States Capitol and their members’ offices.”  

The whole complex is on course to reopen for business as usual Tuesday, which would undeniably be the desire of its elected official tenants.  

Capitol Hill retains more of the feeling of openness and ease of movement than almost any other high-profile facility in the federal government — a mandate from the lawmakers themselves, who insist their working world be perceived as being as accessible to their constituents as possible.  

Even in this era of global terrorism, members confronting record-low approval ratings understand the political risk of giving their own security too much emphasis at the expense of democratic transparency.  

“The Capitol is our greatest symbol of democracy, and these officers serve to protect not just those who work there but also the millions of visitors from all around the world who travel each year to see it,” Speaker Paul D. Ryan said in one of several, bipartisan tributes from members of the leadership to the Capitol Police’ response.  

Those tourists remain free to stroll the grounds and, when Congress is in session, approach those members who choose to walk outside between their office buildings and the Capitol proper. And those who use the CVC are welcome, after passing through a second magnetometer, to sit in the galleries that ring that House and Senate chambers and take in a few minutes of the debates below  

Such visitors are not separated from their elected representatives by any bulletproof glass or other screen — as Larry Dawson, the 66-year-old Tennessee man suspected in Monday’s incident — learned in October when he was able to shout out that he was a “prophet of God” before being removed from the balcony overlooking the House.  

Creating some sort of barriers in the chambers to shield the lawmakers from the spectators has been proposed many times since 1954, when Puerto Rican nationalists fired about 30 rounds from the gallery onto the House floor, injuring five congressmen. But the idea has always been discarded as symbolically poisonous.  

Instead, Congress rallied almost two decades ago behind construction of the CVC as a way to simultaneously improve the tourists’ experience and subject them to security checkpoints long before they can draw near to anyone in power.  

While 9/11 created the momentum and the money to make the center more elaborate and expansive than originally envisioned, the project got off the ground after decades of indecision after the first two Capitol Police officers in history were killed in the line of duty.  

The similarities and differences in the circumstances of that incident put in high relief just how loose the security used to be, and how the procedures in place now may well have saved lives.  

On a Friday afternoon in July 1998, Russell Eugene Weston Jr., a paranoid schizophrenic brandishing a .38 caliber revolver, was able to walk through a tourist entrance on the ground floor on the House side of the Capitol, at the foot of a set of steps leading within 30 seconds to the speaker’s office.  

He walked briskly around the only X-ray machine and magnetometer and fired point blank into the head of J.J. Chestnut, who was the lone officer manning that checkpoint.  

Weston then took off and bolted, seemingly at random, through an unlocked door just a few feet away – which led into another House GOP leadership office suite. There, he shot John Gibson, a plainclothes detective assigned to protect Tom DeLay, then the majority whip, who was in the next room.  

(Weston has never been judged fit to stand trial but is being held indefinitely at a federal prison psychiatric hospital in North Carolina.)  

The architecture in place now, and the procedures that go with it, have made it exponentially more difficult if not quite impossible for a solitary constituent, aggrieved if not mentally disturbed, to push into the Capitol complex and get close enough to a lawmaker to cause bodily harm.  

“I think you have to think that the police are going to do everything they can to keep people safe. But no one can guarantee a risk-free society,” GOP Sen. Charles E. Grassley said when asked about the Capitol shooting before convening a town hall meeting back home in Iowa  

Bridget Bowman contributed reporting.

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