India, Oct. 12 -- A distress call came around 11pm on Sunday. Thirty to 40 people were being held at Najafgarh in southwest Delhi, five or six of them minors, and some claiming to be injured. Within minutes, a message went out to lawyer groups. By the time Shobhit Chaudhary had spoken to the police point of contact, independent lawyers near Najafgarh had been located and dispatched.

"We basically worked on creating a rapid response system for the fraternity," said Chaudhary, a Delhi-based independent litigator. "It is working, but in all honesty there should not be a need for this to be working."

He is part of a legal volunteer network that has worked around the clock over the last few days to help protesters amid mass detentions in the...