But, from late 2023 - coinciding with the escalation of violence in Gaza - Brendan Nugent's focus on X radically shifted from the protection of native forests to the conflict and other political issues.
In one post prior to the 2019 federal election, when Dr Haines won the northeast Victorian seat of Indi, succeeding fellow independent Cathy McGowan, Nugent appeared supportive of her cause.
The now-43-year-old tagged her personal account on the platform, then known as Twitter, in his post displaying political material, which he labelled: "LNP funded anti-independent propaganda."
Dr Haines' official MP account follows Nugent on X, where he has posted prolifically since 2014 under the handle @NotLaoTzu.
In his X bio, he identifies himself as a "plant person", adding: "The world should be run by dogs and children."
For close to a decade, Nugent posted hundreds of times advocating for less logging, the protection of Australia's threatened species and action on climate change.
But from early 2024, he stopped posting about the environment on X almost entirely.
As recently as Sunday, two days before the alleged attack, Nugent reposted an article about an investigation by Italian officials into Israel's defence minister, as well as a video about the trial of British comedian Russell Brand.
He was arrested on Monday afternoon after allegedly using his Toyota Land Cruiser to ram into Dr Haines outside her electoral office in Wangaratta.
He remained in custody but had not been charged as of Tuesday afternoon.
In a string of replies to posts in early 2024, Nugent was particularly active on issues involving Palestine in response to Australian politicians.
Nugent called Prime Minister Anthony Albanese and Foreign Minister Penny Wong "US lap dogs" in reply to a post condemning attacks by Iran on Israel.
"Maybe if you had warned Israel about its attacks the world wouldn't be where it is right now," he wrote.
Nugent responded to a post by Senator Wong in which she said Australia was "clear" Israel should not proceed with attacks on the Rafah region of Gaza.
He replied: "You have not been clear on anything other than giving Israel impunity to kill thousands of children."
Nugent also questioned the impairing effects of long-term cannabis use on drivers, saying opposition to the drug was "mostly ideological".
In February 2018, Nugent posted about attending an anti-logging protest in Strathbogie in central Victoria in which he stated: "No machinery made it in today!"
He later posted asking for funding to support the program to help cover $7000 of fines issued to 10 protesters, including himself.
Nugent was a member of the Our Strathbogie Forest group, which campaigned against logging in the region, but he stopped attending meetings in person around the year 2020.
Many of the group's members were supporters of Dr Haines and reported being highly distressed by the alleged attack on her.
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