Are EVMs tamper proof ?

Can EVMs be tampered ?

It is like asking whether your wife can 'cheat' on you?
How will you answer that?
Yes and no.

After the open challenge thrown by the Election Commission fizzled out with political parties backing out, inspired critics of EVM machines are now clutching to every straw in the wind trying to nail EVMs.
They have found one in an answer to a RTI query from Buldhana in Maharashtra where at one polling booth, the Election officer admitted that a machine had malfunctioned and he had ordered a repoll.

So again the rhetorical question: Can EVMs be tampered ?

Now, Request: Read complete answer before jumping to any conclusion.

Yes, EVMs can be tampered. But process is not trivial. Also, you need physical access to control unit, seal breaking of unit, time and lots of technical knowledge.

One way to tamper is manufacture units which are programmed to record wrong votes (that can’t be the case, as ruling/powerful parties would have never lost). There can be few defective but many of them are found when its checked in presence of candidates’ representatives before voting commence.

Tampering can’t be just done by pressing buttons in some sequence, so it can’t be done in polling booths with so many watchful eyes and within few seconds.

Data is stored in a chip inside control unit, votes are recorded in it using ballot unit. In strong room only control unit is stored and ballot unit is separated. So even if some one get access to strong room (which is sealed and watched by police and representative of candidates) and can replace the seals (as they are sealed), one can’t just reset the votes recorded and record votes again without ballot unit.

It leaves only viable option for tampering is opening the control unit and manipulating the data in chip. That’s why I said time and lots of technical knowledge.

Now, to influence results of election of scale of General Election thousands of EVMs needs to be tampered as one control unit has votes of max 1500 voters. So, practically its impossible to tamper enough EVMs to overturn General Election results.

Note: Whole control unit can be replaced but it will be election tampering not EVM tampering. But again scale at which replacement is required for significant effect is huge and practically impossible.

There are some videos which claims to demonstrate that EVMs can be easily tampered. Those are fake. First you can’t just get genuine EVM used by Election Commission in market to buy and show it can be tampered easily (I will question how the person got EVM?). There are few videos which shows the process on emulated EVM on screen. Come on, that’s ridiculous. One can write such emulators to whatever they want. Even I can write and give you such fake emulator which gives your desired results. Those are not EC official EVM emulators or how EVMs actually work. Those are fake created by some people to just fool people to believe how easy it is to tamper EVM which is not the case.

So to summarize, Yes EVMs can be tampered if you get physical access, have enough expertise and time. No practically tampering is not possible to overturn General Election or Assembly Election results in India.