If a user requests me to delete his account on my forum, do I need to?

i suppose there are specifications while the member registers to the forums "readme" which is agreed by the member
but this could be rare when it comes to legally obligated to do it, it can happen in 1 out of 1k odd members may be 1 out of 10k,
As of now i have never faced such a situation, but i will keep in mind about this.

Also being a forum owner we can add a legal clause in the readme which is agreed by members during registration process in case those account deleting specifications are missing.