Traffic challan

1. legal traffic police has every right to check the vechile and there documents verification

2. if you have done any wrong act only they will fine you with challan which contains a code number mentioned on it 

3. you have to sign the copy and then only he will let you go 

if you have any grievance then contact the toad transport authority of your area and complain about the act with the traffic police name and act of place 

Thank you Mahesh, To your reply point wise:

However,

1. Why do need to detain the documents? They can ask for verification and give the original back?

2. In India, till date we are following wrong traffic light system. Hope you have noticed it. Green, yellow and then red - this is wrong. Correct order is - Red, yellow and green. So by the logic, the challan when you cross road on yello light is wrong......so your contention, that only when you have done anything wrong, only then traffic police will challan you - is wrong.

3. Why do I "HAVE TO" sign the challan? They verified the original documents and in all cases they keep the original documents (if you dont pay amount there and then) so why do I need to sign a wrong statement? They can take the documents with challan to the court and person will go to court and litigate.

Why is that only when I sign then he will let me go? 

You have not answered my question - Do I have right to write on to the challan and then sign?

Please advice

Please share the legal standing on my questions. 

I am not after the corrupt practices prevalent. Please share the correct legal standing on my questions :

1. Do I have a right to write on same challan before signing it? Reason, not always its the fault of citizen but of traffic policmen as well. Signing a wrong challan would directly amount to acceptance of what policemen wrote on to it. So why should I sign a document which contains wrong fact. Instead, I would also like to write my side to it and then sign.

2. And what are the consequences, If I don't want to sign it due to the gross wrong fact contained in the challan?

3. Do I need to submit my original documents with them everytime? why? Will those get delivered at their cost to me in future?

4. Does traffic policmen have right to violate rules to catch hold of person and challan him/her - like coming between the road obstructing the way?

Thank you for reading my questions, but these bug me the most. Appreciate if you could help me in finding accurate legal answers.