I think that there must be an exception for certain crimes, but not all crimes. Otherwise, a murderer, rapist, thief, corporate spy, hacker, etc, could claim that they didn't know it was illegal and probably get off the hook.
The one being discussed is "criminal intent". It's an admittedly fuzzy term, but clearly if you're murdering someone, you have criminal intent regardless of your knowledge of whether it is illegal.
Well... mostly clearly. Clearly enough in the murder case, but there's certainly fuzzy cases. Still, there are an awful lot of crimes on the book that when you lack criminal intent, it doesn't actually make sense to prosecute from either a "rehabilitation" or "punishment" point of view, such as the ones in the article. What did society gain by any useful metric in the orchid case? In fact it lost a lot for no good reason.
Disclaimer -- IANAL, so maybe we can all get some elaboration from an attorney and learn something?
Let's make a distinction between intent and awareness of the law. For example's sake, let's say you've been trading stock off a tip a company insider gave you, which is illegal. At the same time, you don't know it's illegal, but you are consciously trading the stock.
Intent -- You have the intent to trade the stock because you are doing it during the day, awake and fully aware of your actions. You would not have intent if you traded the stock while sleepwalking.
Awareness of the law -- You are not aware that your actions are a crime, despite having an intent to perform those actions. This makes no difference -- you are held accountable for your actions whether you knew they were illegal or not, as long as you were cognizant while you were taking those actions.
IANAL, so again, the language is probably all flubbed. But it's my understanding that intent matters, not awareness of the law. Can anyone correct me if I'm mistaken?