Parliament House is a workplace as well as the organ of our state's democracy. And some of its staff are clearly rattled the day after the alleged bashing of a Protective Services Officer by a man who is believed to have taken the officer's gun and turned it on himself.

One PSO was visibly shaken and emotional as he arrived for work this morning, and is reported to have broken down in tears in the gallery a short time later.

PSOs guarding the building, where traces of what appears to be blood remain on the steps, would not be drawn on their reaction to last night's events, directing inquiries to their media officer. But other security staff detailed to process visitors were distracted, huddled in conversation before a window above the steps and ramp where the alleged incident took place, oblivious to this visitor waiting to have her bag screened before being admitted to the building.

A representative of the procedures office would not comment on the support being offered to staff arriving for work this morning, beyond saying there is an employee assistance scheme that includes counselling is available at all times.

Most of the front steps along Bourke Street at the front of Parliament House are currently behind tall hoardings for building works, with the only pedestrian access to the building's formal entrance via the step's southern corner. As a result, the visibility of anyone approaching from the north is extremely limited.

Premier Ted Baillieu said on Wednesday morning that while he was generally happy about security arrangements, the construction site on the steps had created a potential problem.

"(It) has changed the line of vision around the front steps of Parliament and I think there is an opportunity for a review of that."

It is not the first time questions about potential gaps in the security arrangements at Parliament have been raised this year.

In September, vandals spray-painted a number of swastikas on the Spring Street building at night, including a giant swastika painted over Parliament's bronze plaque.

At the time, the Premier said the vandals may have acted quickly in an area that wasn't "immediately observable from the cameras".

That same month, anti-coal protesters climbed on to Parliament's roof, in broad daylight, and abseiled down the front of the Melbourne building to unfurl a large banner.

Building works were also implicated in that incident. Protester Dominic O'Dwyer told Fairfax Media the group accessed the building by climbing scaffolding at the rear of the Parliament.