In the flashback, when Oliver and Shado are by the river they undress and she is not wearing a bra; when Slade comes to find them, she is wearing one.
Martin Somers cannot be prosecuted on the basis of the confession, because that confession was forced, under duress, and he might have spoken falsely what the hooded vigilante wanted to hear. Any two-bit street lawyer would prove that decidedly in a court of law, let alone the long battery of big shot lawyers of Martin Somers. So, the hush up winding of Martin Somers' case was misconceived.
When interrogating Roy, Laurel threatens him by saying "I could charge you with obstruction [of justice]". DAs don't charge suspects; they prosecute charges placed by the police.