LEIGH SALES, PRESENTER: When Barnaby Joyce was accused of sexual harassment earlier this year, it capped a tumultuous period in his political career.

He'd faced a by-election after revelations of his dual citizenship and his affair with a staff had been exposed including the detail she was now pregnant.

Then came news that a West Australian businesswoman, a former WA rural Woman of the Year in fact, had made a formal complaint to the National Party about his alleged behaviour at a function in Canberra.

The then deputy prime minister denied allegations of inappropriate behaviour, he still does, but the weight of scandal forced his resignation from Cabinet.

Catherine Marriott, a Broome councillor and businesswoman alleges that in August 2016 Barnaby Joyce sexually harassed her.

On the 20th of February this year she made a confidential complaint to the New South Wales Nationals but four days later, details were leaked and Catherine Marriott was front page news.

Her complaint was one of the factors in Barnaby Joyce's resignation. He's always strongly denied the allegations, calling them "spurious and defamatory".

BARNABY JOYCE: There has been a litany, a litany of allegations. I don't believe any of them have been sustained.

I have asked that that be referred to the police. I've asked for the right of the person who's made the allegation and I've asked for my right of defence.

LEIGH SALES: An eight-month investigation by the Nationals ended in September. It couldn't make a finding either way.

Catherine Marriott thank you very much for joining us.

CATHERINE MARRIOTT: Thank you for having me.

LEIGH SALES: Let's just get straight to point, what happened with Barnaby Joyce?

CATHERINE MARRIOTT: I thought long and hard about this and I really have no intention of talking about the incident.

My reasons for that is that I don't want to be someone who is defined by that incident.

I want to be able to have a career where the first thing that people think about when they meet me is not "Oh, that happened to her".

I want to meet and be able to have conversations to create influence with people that I work with, that I will work with in the future without having them think, "Oh, that happened to her.

I don't want to be in a position where I'm a victim. I want to be in a position where I can continue the work that I have and apart from that, I don't want every time I look on Google, to have to relive what happened to me that night.

LEIGH SALES: There would be some viewers watching this who might think, "Well, how can we trust the veracity of what she says from here if she doesn't explain the detail of what happened?"

CATHERINE MARRIOTT: Yeah, and I understand that. My answer to that would be, although I'm not going to talk about the incident, I can talk about what happened directly afterwards which was that I walked up to my hotel room and I burst into tears.

I then couldn't sleep that whole night. I didn't actually sleep for a week.

I rang two of my closest friends and I told them what had happened and they said they couldn't believe it. They were just absolutely shocked and they said, "You can't tell anyone, you cannot tell anyone, you will be destroyed".

LEIGH SALES: So you explained the impact on you is obviously traumatic. Your friends advised you don't tell anyone. What was your thought process about whether you wanted to tell somebody or not tell somebody or go to the police?

CATHERINE MARRIOTT: I ran away from it all and just compartmentalised it and just went "I cannot deal with that".

When it happened he was the Ag Minister, he was a very popular Ag Minister at that time and I didn't, I'm just a little human against a big system and I was terrified.

But I guess when, there was three things that happened that really changed, like I was living with this guilt and this growing anger about the fact that I'd spent my entire career building capacity in other people to stand up for what you believe in and everything and, yet, I didn't have the strength within myself to face up to that.

If I went to the police, it's me versus him, which is a toxic space to be in. It will create no outcome for anyone else. It puts what happened that night on the public record and on top of that, I'm exhausted after eight months.

I would have had to go through a court system which is two, three, four years long. How much would that cost me? How much is that emotional toll and yet I don't get the outcome which I'm looking for which is to create change across Australian workplaces to help raise awareness of the fact that this is an issue that is costly, that does need to make, we do need to make changes.

LEIGH SALES: So you said there were a few things that happened that changed your thinking about whether you were going to report it or not. What were those things?

CATHERINE MARRIOTT: Yeah, so the Me Too movement obviously opened a big can of worms in that space. I still didn't have the courage to say anything at that stage.

The second part was something that I'm really careful with how I word because I don't want to take away from the severity of the cause. Unfortunately, in January this year, a pastoral family lost their little girl to suicide and she, little Dolly Everett left the world with some really wise words far beyond her years which was "Speak even if your voice shakes".

So I was sort of like "Take a good hard look at yourself, what's wrong with you Catherine?"

And the third thing was a friend of mine who knows me really well, knows about the incident and she said to me, "Maz, you've spent your whole entire career building capacity in young people particularly, if you choose to say nothing now and five years from now this behaviour is still going on, will you sleep at night?"

And the answer to that was unequivocally no. I wasn't brought up to run away from things that frighten you, although it took me some time to get some courage.

LEIGH SALES: So once you decided "Okay, I want to do something about this," what did you decide to do?

CATHERINE MARRIOTT: I want to keep it absolutely confidential and so I rang a good friend of mine who is a lawyer, Emma Salerno, and I said "Em, I really want to do something in this space, I don't know how to do it but I don't want anyone to know".

And so she wrote a confidential without prejudice letter to the National Party and then, yeah, all hell broke loose.

LEIGH SALES: And what happened?

CATHERINE MARRIOTT: They leaked it. My name was leaked and that is one of the most frightening things that you will ever have to live through is when you finally, sorry, I said I wasn't going to cry.

Anyway, you live through, you finally find the courage within yourself to stand up for what you believe in and then all control is taken away.

So I had people knowing my name without me being given permission. I was judged for, you know, I don't know how I was judged but the control that I had of my own identity was taken away and that's something that I will live now with for the rest of my life and I think was, you know, I think it was really unfair and it was really horrific.

LEIGH SALES: So in that immediate then days and weeks after then suddenly you're in the centre of this very public discussion, what was the impact on you of that?

CATHERINE MARRIOTT: How could the impact not be anything but monumental?

I was in shock for a fair while, but then I just decided "Look, Catherine, you've had all this control taken off you, life, I believe, is firmly about what you do with situations".

So then I got busy trying to make sure that the system was fixed and was better in future for other people.

LEIGH SALES: Why, after your name leaked, did you then have faith to carry on with the process with the National Party of their investigation?

CATHERINE MARRIOTT: Because how else am I going to get change?

I chose to work with the National Party to change their processes because all control had been taken away from me and to their credit, they've taken it on, they've not only changed their policies and procedures for harassment and discrimination, but they've also, they're going to roll it out across all National Party's in Australia.

They are changing their membership form to reflect the fact that if you are a member of the National Party you agree to abide by that sort of stuff.

So we have now got a positive outcome and we're starting to see some positive change.

LEIGH SALES: How did you feel when the review came back by the National Party and said they couldn't make a determination about your complaint?

CATHERINE MARRIOTT: Look, of course I was disappointed.

I wasn't angry because I'd been angry for so long. I'd run out of my angry.

I sort of had a feeling that that was going to be the case because once I understood their procedures and how they were going to handle it, I hoped that it would end differently but it didn't.

So I guess knowing their procedures, somebody had to have the courage to stand up and go through with it, to prove that the system was broken.

LEIGH SALES: What would you hope now would come from you speaking publicly about it?

CATHERINE MARRIOTT: I would really like to see all the political parties, state and federal, local governments, corporations, both large and small and the not-for-profit sector ensuring that they have solid harassment policies.

I mean, if you think about it, Leigh, the amount that this is costing not only from peoples' confidence and well-being but the economy.

I mean, if you think about it, 20 per cent of people that have been harassed and handed in a complaint are leaving the workforce. That is a phenomenal corporate knowledge loss.

How much is that costing people? Like, can we afford, now that there's been a spotlight shone on this issue, can we afford to not deal with it?

I just think that it is the saddest indictment on the Australian system that the figures are like that.

So let's, as a country, stand together and actually fix it.

LEIGH SALES: Catherine Marriott, thank you very much.

CATHERINE MARRIOTT: Thank you.

LEIGH SALES: That interview was produced by Peter McCutcheon and Callum Denness.

In a statement to 7.30 Barnaby Joyce says he absolutely denies any allegation of sexual harassment, that Catherine Marriott's complaint should have been dealt with immediately and that the process denied him natural justice.

The New South Wales Nationals told 7.30 their entire policy and procedure around sexual harassment complaints has now been reviewed and amended.

You can find the full statements on our website.