I find it strange there was no warning process to include formal reprimands before dismissal. At my previous employer many were caught indoors with analogues during the very cold weather. Not so hard to catch since the odor was present. I was also charged with enforcement of other employees. I would always give one "Unofficial" warning and ask them to step outside. If ignored a formal process was instituted. Even so at least one warning was issued in writing before dismissal. Check the company policy book. You may have a wrongful discharge situation which can be pursued legally.