A 76-year-old woman arrested and charged for trespassing at Liberal MP Sarah Henderson’s office said she’ll be back again to protest against political inaction on climate change, and that “every one in this country should be doing the same to their local representatives”.

Every Friday for the past four months, Caroline Danaher has sat outside Henderson’s office with two deck chairs. In 40C heat or in the rain, her goal is a meeting with Henderson, whose office is in the marginal Victorian seat of Corangamite.

After a redistribution it went from being Liberal-held by 3.1% to being nominally Labor by 0.3%. With Henderson under pressure to regain the Liberal’s hold on the seat, Danaher says it is the ideal time to question her about climate change.

Sometimes, Danaher has gone inside to deliver a handwritten letter for Henderson, a new one each week. The letters cite statistics about climate change, declare climate change an emergency, and request a meeting to talk about what’s needed politically to save the planet. Danaher’s written more than 20 of these, and all remain unanswered.

Facebook Twitter Pinterest Caroline Danaher wrote to Sarah Henderson saying she would continue to protest, whoever was elected on 18 May. Photograph: Caroline Danaher

On Friday, as Danaher and a few of her supporters sat in the waiting area of Henderson’s office, once again having asked for a meeting and delivered a letter, Henderson decided after more than 20 weeks, enough was enough. She called the police.

“There were about five of us and we just sat there and I said I would really like a meeting,” Danaher says. “Suddenly the police came over and said they would lock down the office and therefore I’d be trespassing if I didn’t leave.”

Three of the protesters left. Danaher and one other protester, a 66-year-old man, were arrested and charged. Video taken by one of the protesters shows the pair sitting quietly, waiting for police to arrive. Before arresting the pair, police spoke with Henderson’s staffers, one of whom walked over and tried to convince Danaher to leave.

“I always talk to her staff, we are friendly to each other and they are civil to me,” she said. “And one came out and he tried to talk me into leaving, and I said: ‘I’m entitled to ask for a meeting and I’m not going anywhere’.”

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Danaher and her friend were arrested, taken to the police station, gave statements and were allowed to leave. They are expected to be summonsed at a later date.

But Henderson has met with Danaher before. Several Fridays ago, Danaher was told that Henderson had 15 minutes to spare and would see her. It was impromptu, and Danaher says it wasn’t enough.

“She didn’t listen to me and I didn’t get to say all I had to say.”

A spokeswoman for Henderson told Guardian Australia the meeting went for 20 minutes.

“On 10 May 2019 police attended Ms Henderson’s office after a group of protestors refused to leave and were impeding access,” she said.

Henderson, a former award-winning journalist and attorney, has held the seat since 2013. She is up against Labor’s Libby Coker, also a former journalist, who has twice served as mayor on the Surf Coast Shire Council. The Greens candidate is Simon Northeast, a lawyer and social justice advocate.

Climate is a divisive issue in the electorate. Danaher says sometimes when she’s sitting outside on her deck chair, armed with placards, people will drive by and hurl abuse at her. “They tell me to get a job, which I find very amusing,” she says. But other locals ask her questions.

Facebook Twitter Pinterest Caroline Danaher outside Sarah Henderson’s office in the electorate of Corangamite. Photograph: Caroline Danaher

“They will say to me: ‘I know climate change is happening, but what can I do about it?’”

Henderson’s signage through the electorate has been targeted by climate protesters. She reported the vandalism and theft to police, and has hired security for her final days of campaigning.

Danaher says she does not endorse violence, threats or intimidation. She was compelled to begin the weekly protests after 15 year-old Swedish student Greta Thunberg initiated the school strike for climate, a movement which became global and led to hundreds of thousands of children calling on their politicians to act on climate change.

Danaher says it was a wake-up call.

“She was 15 at the time and I was 75, and that clicked with me. I thought wow, here she is at beginning of her life and here I am at end of mine, yet I have known about this issue since the 70s and I’ve been asleep. I felt so badly about my inaction.”

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Danaher doesn’t know who she will vote for come Saturday. If Coker wins, Danaher says she will be back the following Friday, calling on Labor to do more. But she said she had asked her 12 year-old grandson, Henry, to research the candidates and their policies, and that he would tell her who she should vote for.

“I told him when you have found the candidate you think will make the biggest difference, let me know.”