Police is one of the scariest examples of corruption. India does not have any special laws to prevent corruption. Like every other system it has loopholes which can be taken advantage of. Also, the public perception regarding corruption is rather limited.
Unless people respond strongly by rejecting corrupt people in elections, one should not expect much from the system. I am surprised to see that people in India do not look down upon those who become wealthy by adopting corrupt means.
We seem to be an over-forgiving nation. Being a federal country we have many rungs of political parties which increase the number of power points we have. Therefore, the number of public servants too is much higher than in a country with a unitary system.