I do not know all the specifics of the situation at hand, but my experience with India is that everything takes too long. The sloth in the judicial system should come as no surprise (for better or for worse). I can appreciate India's attempts at being a rational, democratic society. An alternative could be moving towards a more reactionary barbaric society.
When a criminal is caught, the legal system aspires for him or her or they to be innocent until proven guilty. This is the 'right' way for the system to work out. Don't believe me? Then imagine a world where people can frame each other and blame each other for crimes and the justice system has no responsibility to actually carry out justice -- that only the people with the best lawyers can prove that they are innocent. While the current system is very slow and needs improvement (what doesn't in this world?), the focus seems to be on the right thing.
Terrorists and other enemies of the State are other animals altogether. When something really bad hurts us, one of the reactions is to strike back. Blindly striking back is exactly what 'they' (whomever they are) want, because that gives them the evidence they need to breed more terrorists. Any stable civil state would want all terrorists dead on paper. Actually accomplishing this task is more difficult in real life; especially when this may or may not involve people from a number of countries.
Because these cases are so tricky, you have to have everything be certain before you take action. This can't be like making a massive move based on poor intel or poor deductive reasoning. This is the mistake that the USA made -- a number of times: bay of pigs, Vietnam war, Afghan war after 9/11, invasion of Iraq, etc. It is one thing for USA to look like fools in front of entire world for going to war based on incorrect data, it is another thing for USA to look evil and wrong as well. Both of those things have already happened because of pressure for action after being attacked.
America can afford to look like both because they have the most guns, and are very far away from any enemies.
India? India can't afford to look hasty and make quick (and wrong) decisions. World will criticize India, world will put sanctions on India -- and enemies in other nations are very close.
Old children's story says "Slow and Steady wins the race".
India cannot risk making mistakes in how to deal with terrorists. I wish for India to speed up and become more efficient. But I do not wish for India to speed up so it can pretend to be efficient - and end up making life more risky for Indian citizens.
