On the afternoon of April 6, a crowd of residents of Bombay gathered outside Azad Maidan. Actually, they had marched there from August Kranti Maidan, about 7 km away, escorted all the way by policemen. When they reached Azad Maidan, they found that there were other demonstrators there. So they sat down on the footpath and the road in an impromptu rasta roko (blocking the road).
From accounts of several journalists and eyewitnesses, from some film footage shot at the time, it is clear that this was a peaceful gathering.
The police suddenly decided to attack them. They waded into the crowd wielding lathis. People panicked and stampeded, blows rained down, people fell and hurt themselves in the melee. A man filming the events had his camera smashed, his clothes torn. One child was hurt so badly, she died.
On the evening of April 22, another crowd of residents of Bombay gathered, this time on Marine Drive. They staged a rasta roko too. There were police in attendance here too. From all reports, this gathering was also peaceful.
But the police did not attack this crowd.
OK, here are two more details.
The first crowd was largely made up of people from Bombay's slums. They had gathered to protest the demolition of their homes by the Maharashtra Government. The second crowd was largely made up of people who live on Marine Drive and nearby; prominent among them was a local politician, Mangal Prabhat Lodha. They had gathered to protest the rape of a college girl by a policeman in a Marine Drive police chowky.
So: One crowd that's blocking traffic is beaten brutally. The other crowd that's blocking traffic is not.