A protester who blocked the Sydney Harbour Bridge in a protest over climate change has been sent to prison after a magistrate slammed her for her ‘childish stunts’ and ‘selfish emotional’ actions.

Magistrate Allison Hawkins sent Deanna ‘Violet’ Coco to prison for a minimum of eight months after she pleaded guilty to seven charges, including using an authorised explosive not as prescribed, possessing a bright light distress signal in a public place, and interfering with the safe operation of a bridge.

The 31-year-old sat at the front of the public gallery at Sydney’s Downing Centre Local Court on Friday, wiping tears from her eyes as she held hands with her mother and another female supporter.

At 8.30am on April 13, Coco drove a large hire truck along the Cahill Expressway on the Sydney Harbour Bridge and purposefully blocked a lane during peak hour, the court was told.

 Deanna Coco arrived at Downing Centre Local Court with multiple supporters before she was sent to prison. Picture: NCA NewsWire / Nikki Short

While the truck was obstructing traffic, she stood on top of it, held a lit emergency flare and livestreamed the event.

After 25 minutes, police arrived and forcibly removed the protesters from the iconic Sydney landmark, with Coco resisting arrest.

Defence lawyer Mark Davis told the court a ‘salient fact’ in Coco’s case was that she only blocked one lane on the Sydney Harbour Bridge when there were five.

‘One lane was blocked … it was a deliberate decision to only block one lane,’ Mr Davis said.

‘To put it simply, the traffic may have still been moving, there was no suggestion there was backup of traffic.’

The court was told Coco suffered from ‘serious anxiety surrounding climate change’ and her actions were personally motivated, as her boyfriend had been arrested for a similar protest on a football field.

The 31-year-old was arrested after blocking a lane on the Sydney Harbour Bridge

Mr Davis said his client was in a ‘high state of emotion’ and would not have ordinarily conducted the offence.

Ms Hawkins questioned Mr Davis´ defence: ‘Normal members of the community going to work and going about their ordinary business are not entitled to being disrupted because she´s in a high state of emotion.’

The defence lawyer said climate change anxiety was the ‘most prevalent anxiety’ in Coco´s generation.

‘There may be an overwhelming threat of doom, they sense they aren´t being heard, the government isn´t doing enough, it´s leading to these types of actions,’ Mr Davis said.

Ms Hawkins found there was an ‘intended element of planning’ in Coco´s offending.

‘You stopped during peak-hour having obtained a flare and truck, and the banners and glue, to halt peak-hour traffic in the city at that particular time with the aim of gaining maximum exposure,’ the magistrate said.

Coco was in a high state of emotion, the court was told. Picture: David Swift 

‘You knew this was illegal, you knew you would be arrested and you knew there would be consequences.’

Ms Hawkins told Coco she let an ‘entire city suffer’ due to her ’emotional reaction’ and failed to take into account the other people she affected.

She said the 31-year-old´s actions deserved condemnation from both the court and the community.

‘You do damage to your cause when you do childish stunts like this. Why should they be disrupted by your selfish emotional actions?’ Ms Hawkins said.

‘You are not a political prisoner, you are a criminal.’

Coco was convicted and sentenced to 15 months imprisonment with a non-parole period of eight months.

She hugged her mother and friend before she was handcuffed and led out of the court by two corrective services officers.

Her legal counsel immediately filed a sentence appeal and appeared before the same magistrate for a bail application while the appeal was waiting to be heard.

The avid protester attempted to get bail pending an appeal. Picture: NCA NewsWire / Nikki Short 

Mr Davis told the court Coco should be bailed as she had no risk of not appearing in court, while her mother offered up a $10,000 surety.

‘She has abided by all restrictions, she´s shown the court all respect and she has not offended again … she is not a threat to society,’ Mr Davis said.

Ms Hawkins said the court did not jail people lightly and Coco´s offending was the ‘higher end of the range’.

‘It seems it was well and truly open to the court the prospect you would face imprisonment,’ she said.

Bail was refused.

Coco is a serial protester and a member of climate activist groups such as Extinction Rebellion and Fireproof Australia.

She has been before the courts previously for rallying against a mining operation while topless and for setting fire to a pram outside Parliament House.