The police will be failing in their duties if this fella is not
charged. There is absolutely no excuse for pushing an 76 year old
lady or for that matter anyone out of the bus in the manner he did.
So what if he is depressed? He has absolutely no right to take it
out on others. A month’s jail term, followed by a three month stay
in IMH will do him a lot of good.
Obviously a spoilt arrogant brat. I am surprised no one in the
bus gave him a few hard punches to wake him up!
Depression is not as simple as being depressed. 
Please consult your DSM-V. 