Luke 22:68

“And if I ask you, you will not answer.”

Jesus then pointed out to them that were He to question them about themselves and about Messiahship and about the Old Testament Scriptures, judging by past form they would not answer. Indeed He had had enough experience of them previously to know that this was so. See for example Luke 20:7 where they had refused to give an answer about authenticating what was of God, because they did not want to condemn themselves or lose popularity. And Luke 20:41 where they had given no answer at all to an important question about Messiahship, because they had no answer. So what they were asking Him to do was what they themselves would not do, reply openly to what seemed to be straight questions in a possibly critical environment. But He also wanted them to appreciate that their questions were not really straight at all, they were simply just a method of getting their own way and making out that He was in the wrong. There is a certain irony here. For the truth is that Jesus had constantly during His ministry been barraged with their questions, and His real crime was that He had answered them too well.

So Jesus may here well be looking back to previous times when He had sought dialogue with men like those before Him. But it may also be that He had attempted to put questions to them earlier at this very hearing and had been brushed aside, in the same way as He had been before Annas (John 18:22). Either way the intention of His point was in order to establish their perfidy and hypocrisy.