Is it permissible for a husband to allow his wife to travel for study with her female colleagues a distance of 60 km, knowing that it is impermissible for a woman to travel without a mahram, and there is another opinion that permits it?

The majority of scholars hold that it is impermissible for a woman to travel without a mahram (definition), except in cases of necessity. Some, however, have permitted it when there is no fear of fitna. If the wife believes it is permissible for her to travel without a mahram given her safety, then it appears the husband does not sin if he gives her permission. This is analogous to the Shafi'is and Hanbalis not preventing a man from allowing his wife to drink a small amount of nabidh if she believes it is permissible. Nevertheless, if the husband forbids his wife from traveling, she must obey him.