(CNN) -- It was business as usual -- with a twist -- at the U.S. Supreme Court on Monday despite a late-winter snowstorm that blew through the nation's capital and shut down the government.
Public sessions were open as scheduled and security was noticeably tighter following last week's incident in which the justices were secretly recorded during an oral argument and a video posted on YouTube.
It was the first time anyone can recall that happening. Cameras and other electronics are not allowed in the courtroom.
As an independent branch of government, the Supreme Court has wide latitude about its schedule and takes pride in operating on its own terms.
Chief Justice John Roberts makes the call on whether to close the building across the street from the Capitol, and consults senior court staff.
Some court staff, including police, spent the night in the building to ensure operations on Monday, including arguments, would function normally.
Arguments are scheduled months in advance, and canceling or delaying them would create logistical and workload hassles for the high court and attorneys.
All nine of the justices were on hand for Monday's session, which was mostly full with spectators.
Security was noticeably more thorough after last week's incident.
Police gave closer scrutiny to some clothing worn by spectators and reporters, and some were asked to remove their belts.
Cloth-covered tables were also a new feature, along with improved lighting, where pens, notebooks, and personal items were examined in greater detail.
And a wooden sign was prominently displayed next to the magnetometers, warning no cameras or electronics were permitted.
There was no immediate explanation how a camera was smuggled past security last Wednesday.
An advocacy group recorded video of an oral argument that was interrupted by a spectator, who spoke loudly about campaign finance reform, witnesses said.
The group 99Rise.org, which supports campaign finance reform, posted the video on YouTube as part of a protest over the issue.