Former minister Mark McDonald said he could morally justify remaining at Holyrood despite admitting inappropriate behaviour towards women.
Speaking to BBC Radio Scotland, the politician insisted he would stay until the next Scottish Parliament election.
Mr McDonald, who quit the SNP but remains MSP for Aberdeen Donside, is due to return to Holyrood on Tuesday.
He was informed on Monday he would be allocated an office in the parliament’s basement
Mr McDonald had previously occupied an office in the SNP corridor at Holyrood but it is understood he is being moved out of that.
In a statement, Holyrood authorities said the politician would be given temporary office accommodation until the Easter recess.
- Mark McDonald and his whirlwind political career
Mr McDonald resigned from the party in light of the internal inquiry into his behaviour.
First Minister and SNP leader Nicola Sturgeon has urged the MSP to leave Holyrood.
She has been backed publicly by a number of MSPs and MPs representing both her party and opposition parties.
Despite that call, Mr McDonald intends to return to the Scottish Parliament on Tuesday after more than a four month absence.
Suffered a stroke
However, SNP MSP James Dornan has now written a letter to the Holyrood authorities in which he lodges an official complaint about Mr McDonald.
In it he gives details of a member of his staff whom he claims was left distressed by her encounters with the MSP.
He writes: “On one occasion, I had to leave an event I was hosting to escort my staff member to a waiting car as she was sure Mr McDonald was waiting for her.”
Mr Dornan’s letter alleges that last summer the unnamed woman was “so unwell due to stress” that she was admitted to hospital having suffered a stroke.
The politician said she was “under other immense pressure” but this was “compounded by a member who should have known better and who, in my opinion, used his position to harass her”.
A Scottish Conservative spokesman said the allegations contained in the letter were “extremely serious and must be fully investigated”.
During his interview with BBC Radio Scotland’s Good Morning Scotland programme, Mr McDonald was asked if he could morally justify returning to work at Holyrood.
He replied: “Morally I can justify it because, as I have said, my approach to this has been to own the mistakes I made, [but] to demonstrate that I have learned from them and that I am capable of changing as a result and I am asking people to afford that opportunity and I hope that people will do that.
“I accept many relationships are going to have to be rebuilt. Some people will want nothing to do with me and I have to regretfully accept that. But there are some people who I think will want to offer me that opportunity to demonstrate that I have learned from this and that I am changing.
“I want to be able to demonstrate my behaviour has changed and I am not sure that doing that through a by-election campaign is the appropriate way to do it.”
When asked about the constituents who voted for an SNP candidate to represent them, he added: “At the 2016 election I was elected to represent this constituency until the next election and that is what I intend to do.”
Mr McDonald resigned as childcare minister in November after admitting causing a woman “considerable distress” through inappropriate text messages.
But he pledged to stay on as an MSP in order to “continue to serve my constituents to the best of my ability”.
His decision was initially backed by Ms Sturgeon, but the SNP announced on 16 November that he had been stripped of the party whip and suspended as a member while fresh allegations were investigated.
The SNP has confirmed that the investigation examined Mr McDonald’s behaviour towards three women.
It concluded that his “inappropriate behaviour” had been “deliberate in nature”.
Calls to step down
There has been a chorus of objection to Mr McDonald returning to parliament.
Scottish Labour’s Rhoda Grant said Mr McDonald appeared to care more about the “rehabilitation of his image than the wellbeing of the women he is said to have harassed”.
She called for a redacted version of the report into the MSP’s behaviour to be made public and for it to be passed on to the police.
Ms Grant added: “It is not for the SNP to decide what actions are criminal.
“MSPs are in an enormously privileged position and must lead by example, anything less is a dereliction of duty.”
Scottish Liberal Democrat Leader Willie Rennie said he was appealing to the politician’s family and friends to “step in and advise him to stand down before he causes the victims any more distress or himself any more damage”.
Scottish government minister Keith Brown has also echoed the approach of Ms Sturgeon by saying: “If you concede the point that you have acted inappropriately, and you think that has been sufficiently bad that you feel you have to resign as an SNP MSP, I think the logic of that means that you should resign as an MSP as well.”