The TV star and qualified lawyer – who rose to fame as the star of reality courtroom show Judge Rinder in 2014 – made an impassioned speech on the ITV breakfast show in favour of the Criminal Bar Association’s (CBA) strike over current fees for legal aid advocacy work.
Rinder, 44, said: "If I were – I am – still a member of my great chambers, I would be, without question, on strike."
He went on: "I’m not the youngest members of the bar, that start the bar in over £100,000 of debt and on £12,000 a year.
"Let’s talk about what democracy we are. If there’s no access, no rule of law… our justice is meaningless."
The practising lawyer, who specials in international fraud, added: "Lawyers who do this sort of work – not the fat cats – the reality is, they don’t want to strike.
"They don’t go into it to be rich. They go into it because they believe in this country and the rule of law."
Rinder competed in Strictly Come Dancing in 2016 partnered with Oksana Platero.
He is a close friend of the actor Benedict Cumberbatch and was best man at his wedding.
He began co-hosting Good Morning Britain earlier this year, as part of a rosta of rotating co-hosts since Piers Morgan quit the show.
Rinder was hosting the show with Kate Garraway for the first time, and began the show by making a gushing tribute about her strength in caring for husband Derek Draper during his long battle with coronavirus.
He said: "First of all you're sunshine in human form. I just want to say more than anything else you model the possibility against the backdrop of darkness of being light in every sense.
"Your capacity to use the platform you have for change, for authenticity just makes me proud to know you."
Garraway looked overwhelmed as she replied: "Oh my God, that's so lovely. I'm gonna cry."
Watch: Strictly's Oksana reveals how Rob Rinder helped her grandparents at Ukraine border