Helen Kvelde has been protesting in the Sydney CBD since the Vietnam War, but fear of jail time has halted her 50-year-long resistance.

"I am terrified, angry and grief-stricken about the climate emergency," she wrote in an affidavit.

"But I am so intimidated at the thought of arrest and going to prison."

Ms Kvelde and fellow "knitting nanna" protester Dom Jacobs have taken the NSW government to the Supreme Court after tough anti-protest laws were rushed through state parliament last year.

The laws were introduced by the former NSW coalition government with the support of the then Labor opposition following a series of environmental protests which disrupted Sydney traffic in 2022.

The new laws ban protesters from gathering around major facilities and train stations, and protests that block others from using those facilities.

The Environmental Defenders Office representing Ms Kvelde and Ms Jacobs argues the laws impinge on political freedoms.

"The very purpose of these laws is to deter people from protest action and it is having that effect," Stephen Free said at a Supreme Court hearing on Wednesday

Mr Free said there was a significant chance of protesters accidentally blocking entrances when protesting in the Sydney CBD, meaning they would risk arrest.

NSW Solicitor-General Michael Sexton argues the pair do not have the legal right to challenge the laws, which Mr Free argues is "artificial".

Both Ms Kvelde and Ms Jacobs, who sat at the back of the Supreme Court knitting silently as their affidavits were read out, said they felt uncomfortable and fearful about going to protests since the new laws came into effect.

"There have been actions in Sydney that I have not gone to out of fear of being arrested," Ms Kvelde said in her affidavit.

"I'd much rather be growing vegetables and tending to my garden than protesting, I just feel there is no other choice."

The two-day hearing continues in the NSW Supreme Court on Thursday.