AI in the legal field could be useful for assisting an actual legal professional in compiling precedent based against on-the-books laws, so long as it cites sources and they verify them.
In the medical field, it could be useful for spotting anomalies between multiple images such as X-rays or cross-referencing medical documents WHEN USED BY A PROFESSIONAL.
But the thing is, it should be a tool - carefully used - to enhance the existing profession, not replace actual professionals.