What is the term for someone who assists or encourages criminal intent?

The term that describes someone who assists or encourages criminal intent is "abettor." This term specifically refers to an individual who aids or helps another person in committing a crime, often by encouraging or facilitating the criminal act. An abettor plays a crucial role in the commission of the offense, as their support can significantly influence the actions of the principal offender.

While "accomplice" is a term that is also relevant, it encompasses a broader role that includes anyone who takes part in the commission of a crime, whether by directly participating or assisting in some capacity. However, "abettor" more precisely emphasizes the encouragement or support aspect, which aligns directly with the question about encouragement of criminal intent.

The other terms provided do not capture the specific legal connotation associated with involvement in criminal activities. For instance, an "advocate" typically refers to someone who publicly supports or recommends a particular cause or policy but doesn’t imply any involvement in criminal activity. Similarly, an "ally" refers to a supportive partner or friend and does not inherently involve criminal implications.