Do both sentences have the same meaning

Question

Chris did not tell the truth when he was speaking to Martin

vs

Chris was not telling the truth when he spoke to Martin.

Do both sentences have the same meaning ?Which sentence is the best?

I think in the first one the fact of not telling the truth is only a point of time may be it last one minute then they talked about another subject during 5 minutes where as in the second sentence the fact of telling the truth did last all the speaking What about Chris did not tell us the truth when he spoke to Martin, does it mean that the fact of not telling the truth lasts the same time as the speaking

Answer 1

It's a matter of "focus on the action" vs "focus on the end result". The first sentence stresses the final point - it didn't happen whereas the second sentence stresses the action - throughout the whole time it wasn't happening. – SovereignSun

Answer 2

The choice of a continuous or not does not usually reflect an objective difference in the facts. You cannot conclude from the speaker's choice how long an event lasted. All four possibilities (did not tell or was not telling; and spoke or was speaking) are possible in this case and they can all refer to exactly the same events, taking the same time.

The difference is how the speaker is choosing to focus on those events: whether they are choosing to focus on (not) telling the truth as an extended event or not; and whether they are choosing to focus on speaking as an extended event or not.

If the speaker chooses not to do this (i.e. chooses the simple past) it does not imply that the event was very short, just that they are not interested in conveying its temporal nature, but only that it happened (or didn't happen).