The video of the incident which is all over the social media shows the Liverpool legend lose his cool and spit out at a 14-year-old Manchester United fan who was sitting on the passenger seat of the auto with her window down.
Carragher was goaded in the aftermath of the Anfield club's 2-1 defeat to Manchester United on Saturday and lost his cool, winding down his window and spitting at the passenger side of another auto.
Murphy said: "There is no way I can come on here, no matter how much I respect him, and say what he has done is not wrong".
Carragher described his actions as a "moment of madness", adding: "I have no excuse and it's devastating for the family involved and my own family".
Carragher had initially told The Mirror: "It was a bit more than, "Hiya Jamie, it was 2-1". Carragher then winds down his window while the girl's dad winds down his passenger-side window.
In the video the father of the girl can be heard shouting: "Unlucky Jamie lad".
Just hours after the footage emerged, Carragher tweeted: "Totally out of order & Ive apologised personally to all the family this evening". It's not something I've done before and not something I'll do again. If someone had done that during the game, I would have vilified them. "Looking at her, you know she is a child", she said. It doesn't matter who you're spitting at.
Asked if he had seen the girl in the auto, he replied: "I didn't to be honest, she was leant back". I lost my head.More news: SIPRI: Conflicts fuel weapon deliveries to Middle East, Asia
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The incident took place after the game on Saturday and Carragher spat at the man and his 14-year-old daughter, who was also in the auto.
JC: I've got a daughter exactly the same age and it's hard to find the words I'd use on how I'd react to that or what I'd say to that person if I ever bumped into that person or something. "That devastates me more than anything. It's been something we all could have done without but all I can do now is apologise".
Carragher met with bosses of the broadcasting giant in London on Monday in the wake of the incident which took place on Saturday afternoon. It is vile but let me assure you now - I would have preferred Lucas Neill to have spat at me the day he broke my leg in September 2003!
"That family won't be used to the media storm and being dragged into it". Hopefully I can get the chance again to apologise or maybe meet up with the family to show how sorry I really am.
Will he stay as a Sky pundit?
Carragher wrote: "As usual, there have been a number of people who have said, 'It is the worst thing that can happen on a pitch".
Asked about his future with the company, he said: "We've met up today and it was about finding out the facts".
"I think it's disappointing because he's a good pundit but you just can't condone that".
JC: Yes - and that's my biggest sort of regret.