The fallout from the case was described as a "danger" being taken into account by a team tasked with drawing up new policies on sexual harassment at the Parliament.
MSPs, along with their staff, are now to be offered training on sexual misconduct and the inappropriate use of "banter."
Former Nationalist MSP McDonald has since returned to Parliament as an independent, despite accusations of non-physical harassment. He has admitted his behaviour fell below acceptable standards.
"Do you think a scenario where an MSP can admit to sexual misconduct or sexual harassment and can continue to work in the Scottish Paraliament building - do you think that will hinder people coming forward to make a complaint?" Mr Arthur said.
Mr McGill said: I think there's every chance that that would be the case.
"I think you're asking us to make a value judgement here which is probably not appropriate for us to make. But that would be a danger that we would be taking into account when we would be looking at polices and speaking to people about what these policies should provide."