What is the ruling on shunning a brother who was accused of attempting to assault his wife, even though he denies the incident?

A woman must cover her body from non-mahram men and avoid being in seclusion with them, especially the husband's relatives like his brother and uncle, because the Prophet, peace and blessings be upon him, said: "The in-law is death." This is because leniency in dealing with them leads to evil and temptation, and because they are not mahram. What the husband's brother did is a reprehensible evil, but it is not appropriate to continue shunning him. Rather, one should maintain ties with him while emphasizing to your wife how she should interact with him.