To find information regarding the impossibility criminal defense argument, try searching the phrase impossibility "legal defense" (keep the quotation marks) in the Library welcome page search box:
Another possible search phrase is: "factual impossibility" "legal defense"
An additional search can be conducted in ProQuest Central. To find that database, click on All Databases located on the right hand side of the Library's home page. ProQuest Central is a featured database, and is close to the top of the list.
Within the database, search this phrase exactly:
"legal impossibility" OR "factual impossibility" defense ethics
Be sure to use the quotation marks as shown. That way, the words are more likely to be searched together.
Contact the Library for further assistance.