Whether answering questions based on guessing is considered lying
31-12-2017 | IslamWeb
Question:
We need to obey the laws of our country if they do not command us to commit a sin. So if I am learning for the driving test and the question is something like "What are you not allowed to do?" and I do not know the answer but ponder and answer what I think is most likely, am I lying or saying that something is halal or haram without knowledge? Is this allowed?
Answer:
All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
Lying is to make a false statement that is contrary to the reality. An-Nawawi 
wrote, “Lying means making a false statement contrary to the reality, whether it is done intentionally or out of forgetfulness or mistake.” [Sharh Muslim, 1/94]
Al-Lubaab fi ‘Uloom Al-Kitaab (6/420) reads, “Lying means narrating what is contrary to the reality, whether the speaker knows that what he is saying is false or not.”
Hence, if you were mistaken in what you said, it falls under the definition of lying. However, it does not necessitate bearing a sin if you had pondered and answered with what you believed to be most likely true.
As-Saffaareeni wrote in his definition of lying and which type of lying is sinful, “Lying means narrating or stating what is contrary to the truth, and deliberateness is not a condition in this regard. It is true that if it is deliberate, then the liar bears a sin for it, as the author of Sharh Muslim said and underlined that this is the view of Ahlus-Sunnah. The author of Al-Aadaab quoted it from him and did not oppose it; rather, he said that the person does not bear a sin for it because he did not lie intentionally.” [Sharh Al-Aadaab]
This is not considered saying that something is halaal or haraam on your part, because you are speaking about what you believe to be most likely allowed according to the traffic system, which was set up by people as a result of their own efforts of reasoning in order to serve the public interest.
Allah knows best.