Thank God, there are watchdog bodies like the Karnataka Election Watch Committee (KEWC) that keep a tab on the candidates' data. (I get to know about KEWC activities because its convenor Prof. Trilochan Sastry teaches at IIM Bangalore).
KEWC is committee of Eminent Personalities and is a Non-Partition and a Non-Political one. The purpose of the committee is to inform the voters about the candidates and helping them in making better and informed choice in exercising their franchise in the coming elections to Karnataka Assembly and the Indian Parliament. You can see the following details on Karantaka candidates at KEWC (/Janaagrha) site :
List of candidates with criminal cases from BJP, Janata Dal, Congress and Independent parties List of criminal cases against candidates from various parties Candidates with Nil Assets or Not Declaring Market Value Candidates with High Total Assets Candidates with over Rs.25,000 Government Dues Lok Sabha Karnataka Phase 1, 2004 - Candidates with Criminal Cases