According to The West, Porter's ex-wife Lucy Gunn joined the thousands of protesters marching through Perth's CBD.
Two specific incidents in federal parliament triggered the nationwide marches, one of which involved Porter.
The Attorney-General is on medical leave after he was accused of a historic rape, allegations he strenuously denies.
Another cabinet minister, Defence Minister Linda Reynolds, is also on medical leave after her former staffer Brittany alleged she was raped in Reynold's office.
Infuriated by both situations, a Melbourne academic kicked off a grassroots movement to get women protesting.
Janine Hendry, a Melbourne academic, designer, entrepreneur and single mum, asked on Twitter whether it would be possible to form a ring of people around Parliament House as a silent protest from "extremely disgruntled women". She got her answer — it would take almost 4000 people to make it happen.
Since then the idea has morphed into collective action across the nation. More than 85,000 women across 40 locations are expected to march in major cities as well as numerous country towns like Wollongong and Bunbury.
Hendry said she was fed up with the "woeful behaviour" of the government in response to sexual abuse allegations, ongoing discrimination and a lack of transparency and people would no longer be silenced on injustices.
The 58-year-old told The Sydney Morning Herald that the idea for the Parliament House protest was sparked after Brittany Higgins went public with allegations that a Liberal staffer raped her in the Defence Minister's office.
She said it was also spurred on by the historical rape allegations made against Attorney-General Christian Porter, who has categorically denied the claims, and the shocking testimonies collected by Chanel Contos from thousands of students across Australia about a chilling culture of normalised rape and sexual assault.
While Hendry thought it might have just been seven of her mates standing outside Parliament House with placards, the idea has seen a groundswell of support, including from some big names. Australian TV presenter Julia Zemiro will MC the Canberra protest and author and commentator Jamila Rizvi will speak at the Melbourne march.
"Historic change is in the air. Women who have never marched before are joining us in action. Women who have been marching their whole lives are still here. There are people from every political party and no political party," Hendry said.
Former federal MP Julia Banks, who accused colleagues of badly bullying her and quit politics, and independent MP Zali Steggali have both promoted the marches on Twitter.
Federal Labour MP Andrew Leigh tweeted that his office would be closed today so his staff could attend the march at Parliament House.
But offers from politicians who want to speak at the marches have been knocked back by Hendry, because she wants the events to be apolitical and focused on change, she said.
There are more than 11,000 people following the March4Justice Facebook page and over 9000 on Twitter.
However, the original idea for the Parliament protest had to be canned.
"We are sadly unable to circle Parliament as planned due to permit and Covid restrictions and advice from our experienced organisers but we will make an impact by showing up in our thousands Join me and let's say #EnoughisEnough," tweeted Hendry.
People are being asked to keep Covid-19 safe on the marches by wearing masks and observing social distancing. They are also being encouraged to wear black from head to toe.
The movement will also present a petition to Australia's Parliament, demanding action on gendered violence. It calls for a federal Gender Equality Act, independent investigations into all cases of gendered violence and increasing public funding for gendered violence prevention. It also demands the 55 recommendations from the Australian Human Rights Commission's 2020 report into sexual harassment in Australian workplaces be implemented.