Remember, Lead Detective Sprague claimed not to recognize the dog walker who let his murderer into the building. Never got his name, or talked to him, supposedly.
Sprague also claims to not recognize the name Chris Dahl, who their star witness told Sprague is the one who set up the murder.
In a rational world, the lead Detective would have looked up the name Chris Dahl immediately after Julie Madara said he set up the murder. And in a rational world, he would have immediately seen Chris Dahl's attorney was also Julie Madara's attorney, the attorney her letter said to contact to find out what Chris Dahl did.
In a rational world, Lead Detective Sprague would realize Mandi's attorney Rentz took a bribe to hide that Madara's story came from popular local attorney Adam Reiss. And in a rational world, Mandi's attorney Rentz would then keep quiet about Sprague and Athaide, and Rentz's local friend Smolarek, faking all the evidence.