The court ultimately sentenced the husband to five months, finding that intentionally recording the footage went beyond what could be justified by his attempt to prove an affair. However, the man can choose to have the sentence converted to a NT$150,000 fine, which equates to over $4,700, and can still be appealed.
So the problem is he recorded too much of it, I guess?
Never thought you need a permission to record other people at your own home, but it does make some sense.