I looked into this question after our call today and received the following answer.
Short of coding it in HTML you can not do this in Informz. And you shouldn't - text should never be fully justified anywhere other than in print (though really even not then anymore), for a variety of reasons, including multiple accessibility reasons.
This is a great article explaining why you shouldn't do it.
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Tirza Austin
Senior Manager, Online Community
American Society of Civil Engineers
1801 Alexander Bell Drive
Reston, VA 20191
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