Consider
BELX = A fictitious company which makes EVMs
CECX = Person in charge of dispatching EVMs
CongressX = a hypothetical party which wants to get benefited by tempering EVMs
Step-1 : The EVM manufacturer makes 3 types of EVMs
- Type1 - Honest EVMs
- Type2 - This EVM will increase the votes of the candidate who got second highest votes and decrease the votes of candidate who got highest votes
- Type3 - This EVM will increase the votes of the candidate who got third highest votes and decrease the votes of the candidate who got highest and second highest votes
- Group1 : where congress is sure to win
- Group2 : where congress is sure to come no. 2
- Group3 : where congress is sure to come no. 3
- Group4 : where congress is sure to come not in no.1 to no.3
Step-3: CECX has to dispatch EVMs as follows
- It will send Type1 EVMs to constituencies in Group1 and Group4
- It will send Type2 EVMs to constituencies in Group2
- It will send Type3 EVMs to constituencies in Group3
Hence, the EVMs will favor CongressX.
Example : in Gandhinagar seat, CongressX is sure to come no.2 and BJP is sure to come No.1 So if Type-2 EVMs are sent to Gandhinagar Constituency, then CongressX will win. Now sending such EVMs to Gandhinagar will expose the game as BJP leads by a huge margin. But in seats where picture is not clear, CongressX can win by sending EVMs of Type2 and Type3.
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The moral of the story is : there are simply too many ways to rig EVMs. So we have no choice but to get rid of EVMs and use paper ballots with camera in booth.