Only two possibilities:
Garland, top LEO of the nation, and life-long DC legal apparatchik - had NO idea that the courts would look closely at his appointment of some guy off-the-street to prosecute a former President? If so, he’s a complete idiot
OR - he expected it, and did it anyway. Which means it was simply a planned media psyop, political prosecution, and election interference.
Garland was sooo pis*ed his SCOTUS appointment failed, he became unhinged, as Biden would say. He went off the deep end, decided to break laws to get even.