During the trial against Oliver Queen, she questioned not just him, but also several people associated with him such as John Diggle, Dinah Drake, Dr. Elisa Schwartz, Rene Ramirez, and Felicity Smoak to testify about the identity of the Green Arrow and their associations with him. All of them admitted to have some association with him, but denied that Oliver is Green Arrow. Rene however, admitted his identity due to the fear of Diaz's presence in the court with his daughter, Zoe. If Rene said otherwise, Diaz would have killed her. When Oliver took the stand, the Green Arrow crashed through the skylight, revealing himself as Tommy Merlyn back from the dead.
Tommy testified to her that he faked own death and that Oliver is falsely accused. He was later taken away by police. In actuality, Diaz' men were rescued by John and Rene, and was revealed to be Christopher Chance. Somewhat unconvinced about Tommy's confession, Alexa further questioned in trial by calling Laurel Lance to testify in the case. Laurel eventually admitted that Green Arrow is Tommy Merlyn, thereby distancing from Diaz due to his appalling methods and for reluctant love for Quentin Lance as her "father". After questioning all people in the court, the jury convicted Oliver as guilty.
Oliver's lawyer, Jean Loring, then called for judgement notwithstanding verdict procedure to convince judge C. McGarvey of nullifying conviction of Oliver. Although judge appeared to decline, he suddenly agreed to release him; this was actually Christopher disguised as him while the real McGarvey was kidnapped by John and Rene since McGarvey was connected to Diaz and his criminal organization.
Like the other lawyer, Jean Loring, Alexa is a highly professional lawyer and prosecutor who solved some of the most challenging cases in her career, she puts questions to witness in the court, but her method of work appears to be more objective and sharper than to Jean; due to Oliver's activities who appear to be heroic (apparently little agreeing with it) but also considering them as criminal, as a prosecutor, she was almost close to discovery of Green Arrow identity when questioning Rene, but when Green Arrow arrived in court, revealing as Tommy Merlyn, Alexa was further confused in that situation. But she was somewhat unconvinced and continued to solve this case by inviting Laurel Lance who admitted that Tommy is Green Arrow.
It is unclear if Alexa was connected to Diaz or not since there was no mention or hint of the connection, but it could be that she is just a lawyer who works own job in accordance to the law and having no personal hatred or despise to Oliver, only conducting about what is right and wrong in Oliver's case and in general.
Even Alexa was a little bit surprised about the judge's methods during Oliver's trial (both on real McGarvey and false McGarvey) despite losing the case, she is probably an honorable (if tough) individual who works professionally as a lawyer, unlike the corrupt judge McGarvey who is revealed to be working with Diaz and having a possible despise to Oliver as mayor.
- Master lawyer: Alexa is a highly skilled lawyer, as she nearly defeated Oliver Queen's legal team during his trial.