There was a story in the news recently about a man that Pope Leo said had experienced "a miracle" of healing when he was born. According to the story, the man had recently been arrested. So the article claimed that Pope Leo jumped the gun. There is a lot of presumption in a claim like that. It appears to presume that no one who does something bad can experience a miracle; which is clearly not correct.
God can do a miracle anywhere He wants, and He can have anyone He wants experience that miracle. A person who commits a grave sin (presuming that being arrested means that an actual sin was committed--and that is not always the case) is not eliminating himself from the experience of a miracle. In fact, we do not know the behavior of every person Jesus ever did a miracle for but it is perfectly likely that many of them committed grave sins soon after the miracle.
When God chooses to grant a miracle, there is a certain responsibility that goes with it. We are expected to live in accordance with that great grace that we have received. It is like someone who converts and becomes Catholic; there is no presumption that that person will never fall away from that position. Of course, those who do receive miraculous intervention in their lives have a greater responsibility to live faithfully and be thankful to God; but not all do so.
There is nothing about being arrested or committing sins which negates the Holy Father's estimation of the miraculous; if a miracle occurred, then a miracle occurred. The whole situation is merely one more evidence that God allows grace to be given to good and bad people, and that sometimes good people turn bad, and bad people become good. Let us always thank God for His grace, and do our best to live in accord with it.