CROWDS gathered to protest against Gerard Baden-Clay’s murder conviction being downgraded to manslaughter have booed images of the Brisbane wife-killer on display in the city’s CBD.

Brisbane's King George square is a sea of yellow as hundreds of people have gathered together to protest, many wearing Allison’s favourite colour.

Today co-host Lisa Wilkinson was one of the many prominent personalities leading the call for Queensland’s Attorney-General to appeal the decision, which left many in the community stunned.

Opening the rally, the television personality addressed the crowd saying: “Like all of you I have so many questions”.

Wilkinson called on the Queensland governemnt to appeal the decision made against Baden-Clay, and to amend legislation to that the same thing would never happen again.

She commended the crowd for expressing the right of Australians to disagree with judges’ decisions, and called on governments to “create new laws in accordance to the will of the people”.

“This is how progress is made. If enough people are unhappy with the law as it stands, the people have the right to ask their elected officials to create news laws in accord with the will of the people.”

Supporting the rally is Queensland senator Glenn Lazarus and Bruce and Denise Morcombe, the parents of murdered schoolboy Daniel.

"Hopefully in the days, weeks and months ahead we will get the answers we need"- @Lisa_Wilkinson #DoingIt4Allison pic.twitter.com/ccLOKducpj — Nine News Brisbane (@9NewsBrisbane) December 18, 2015

It comes as a petition urging a government appeal appealed reaches more than 100,000 signatures.

Baden-Clay, who was last year sentenced to life in prison for murdering Allison, had his conviction downgraded to manslaughter on appeal earlier this month, sparking community anger.

Domestic violence campaigners including Rosie Batty said the court ruling sent the wrong message to perpetrators, while Acting Justice Minister Peter Dutton said the law was an “ass”.

“We need women, men and children to show that domestic violence must stop. We need to let our political leaders know the social and legal structures designed to support and protect against domestic violence are not working,” a Facebook page for the event says.

Olympian Libby Trickett, who will also be attending the march, told the Nine Network the protest was about showing support for Allison and women trapped in domestic violence situations, and capturing the attention of politicians.

“I was shocked and disappointed with the results from the legal system,” she said.

“We never want to see this happen again and we don’t want the opportunity for this potential situation to occur. Hopefully in the future we can align the law with our moral values and moral judgment within the community.”

Queensland’s Premier Annastacia Palaszczuk has urged people to be patient as the state’s Director of Public Prosecutions (DPP) considers an appeal.

“This matter is an extremely emotional issue for many people across our state,” Ms Palaszczuk said on Thursday.

“But I want to reassure the Queensland public that the DPP is examining this issue in detail.

“I know I’m asking Queenslanders and the public — the families out there — to be patient, but we have to let the DPP do its job.”

Ms Palaszczuk indicated she would not attend Friday’s rally.

@doingit4allison Bruce and I will attend the rally this Friday pic.twitter.com/j7r6vt5AIT — Denise Morcombe (@DeniseMorcombe) December 16, 2015

Legal groups have defended the court’s decision however, calling the public reaction “hysterical.”

Terry O’Gorman, vice-president of the Queensland Council for Civil Liberties, said today’s rally was a “disturbing” attempt to put political pressure on the justice system.

“There is pressure on the DPP to fall into line with this almost manic public reaction to this verdict,” he said.

“You do not have a murder case or any other case decided by who can yell out the loudest in the media or otherwise about their disagreement with the verdict. This verdict was handed down according to the law of the land and those who don’t like it have to cop it because that is the law.”

At a Christmas function in Brisbane, Queensland’s Chief Justice, who is one of the judges who granted Baden-Clay’s appeal, praised the state’s politicians for putting the court’s independence ahead of “populist considerations”, Brisbane Times reported.