Victoria's upper house president Bruce Atkinson says the physical clash between independent MP Geoff Shaw and protesters outside parliament sets a dangerous precedent.
Mr Atkinson said he was concerned about protesters touching MPs on their way into parliament.
"Members can't be impeded and it sets a very dangerous precedent," he said.
Mr Atkinson said Tuesday's incident involved an elderly man, but the situation could be quite different.
"It could be any member of parliament and, indeed, it could be a young rugby player who in fact is a lot more vigorous."
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The Legislative Council president said MPs needed to have a safe workplace like anyone else and the issue of having a dedicated entrance to the parliament building just for MPs needed consideration.
"If we can't get members safely in and out of the building when they are going about their proper business, or indeed staff, then we may well have to look at a separate entrance.
"The reality is, there are consequences for these sorts of incidents and inevitably our responsibility as presiding officers, the speaker and myself, is the safety of members and staff.
"That's first and foremost."
Parliamentary speaker Ken Smith says it is a contempt of parliament to interfere with an MP entering the building.
Transport Minister Terry Mulder said he and the premier met with the taxi industry protesters before Tuesday's incident.
"We parted, I thought, on pretty good grounds, so I was a bit surprised to see them back here, protesting in front of parliament again."
Health Minister David Davis said the incident was "deeply regrettable".
Treasurer Michael O'Brien said people had a right to protest.
"But I think they should be careful about taking it a bit too far and obviously what happened was a bit unfortunate," he said.
"Obviously it would've been better if the whole thing hadn't have happened."
Victorian Greens leader Greg Barber said the incident was a distraction from more important issues.
"There's fair dinkum serious life and death issues going through this parliament, while everyone seems to be excited about the antics of one not very funny clown."
