The case hinges on whether Salman, 31, knowingly helped her husband, Omar Mateen, plan the attack at Pulse nightclub in Orlando. She has pleaded not guilty to charges of aiding the support of a foreign terrorist organization resulting in death and obstruction of justice. She faces life in prison if convicted.
Jurors on Thursday watched a video timeline of the massacre, which included graphic footage recorded by the nightclub's surveillance cameras.
Jurors were also shown graphic footage captured by police body-worn cameras.
The videos shows Mateen shooting people in the nightclub's main area. Some ran, some fell. He was seen walking from room to room and shooting more people before heading back to the main area and firing more shots.
Salman turned her head away and wept while the videos were played.
"I feel like he is the devil in a human being's body," Susan Adeih, Salman's cousin, said outside the courthouse. "I feel so bad for the families. For Omar, I don't really give a damn. I wish Omar would burn in hell. That's how I feel."
Prosecutors showed jurors photographs of the nightclub's restroom, which flooded after police damaged water pipes while breaching a wall. Evidence was submerged in several inches of bloody water.
Although the photos and video are hard to forget, WFTV legal analyst Bill Sheaffer said that showing them to jurors so early in the case could give defense attorneys a slight advantage.
"You have days and weeks for the shock effect to wear off," he said. "And then the jury concentrates on the facts, not on the emotionalism of the video."
Prosecutors on Thursday called to the stand Fort Pierce police Lt. William Hall, who was sent to Mateen's apartment to check for bombs and booby traps.
When Hall arrived, Salman exited the apartment with her 3-year-old son.
Salman at first refused to allow investigators to search her apartment and her car, but she changed her mind while they were trying to obtain a search warrant.
Hall said he made a tactical mistake by allowing Salman to go to her bedroom alone to change clothes. When he brought up Orlando, before mentioning the attack, Salman asked if they were going to take her to Walt Disney World -- something that wasn't included in his report.
Hall didn't ask Salman if she knew where her husband was or if he was alone, which was information that could have saved lives, he said.
FBI Special Agent Chris Mayo, who interviewed Salman in a police car, testified that he took her to an FBI field office and sat her in a large conference room so she and her son would be more comfortable.
Mayo said it was a fluid situation, but defense attorneys will argue that agents didn't initially perceive her as a threat.
Salman never asked what happened to her husband, he said.
Mayo said he didn't record the interview because it wasn't an interrogation, but in hindsight, he probably should have.
Testimony is scheduled to resume Monday.