Mayoral candidate Bill de Blasio said he wants to go "back to the drawing board" when it comes to outer borough taxis. But why? And what would this plan entail?

De Blasio is offering few details on why he wants to halt the green cab program.  The city's on track to sign up 6000 drivers this year. It's popular with drivers like Victor Alvarez, who says the permit number makes his riders "feel safe." A second driver says passengers like having a meter. 

De Blasio counts yellow taxi medallion owners among his biggest backers.  

So far, he isn't answering questions about what would happen to already signed-up green cab drivers, or how the city would replace the hundreds of millions in revenue generated by the sale of green car licenses. 

Listen to Brigid Bergin's report by clicking the audio player.