It had been a tradition in Congress Party to protect corrupt people and to include them in their party (latest addition being Azhar). Is it the corrupt individual or the corrupt system they are protecting? What fear drives them to such activities?
Oncea tiger tastes human blood, it will go for it only. Azhar has made millions from the cricket by hook or by crook and that very velocity of flow of money in this lucrative profession cannot be had from any other profession thru ethical means, except, from the Politics.
Hence one will not hesitate to invest any amount of money to have a nomination from any standing political party. Good guys seldom opt politics. Given the tainted stature of Azhar or anyone that matters, any political party will offer him a nomination against 'an asking payment' and being a proven manipulator, Azhar can deliver goods also as expected by the party. Hence any political party will admit such guys for an e.g., even Sanjay Dutt, whose storey is well known across the world. He is now GS of Mulayam Party,having unable to stand in the election. So let us not blame Congress alone.
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Once our Chief Minister told in a meeting that corrupt officers are very hardworking and intelligent and they apply their mind to find solution to every problem. This might be the cause for what you say.