While testimony presented by the defense Monday in the trial of George Zimmerman focused on whose voice can be heard in the background of a 911 call made the night of the deadly shooting of Trayvon Martin, the courtroom legal maneuvering focused on key pieces of evidence.

[Editor's note: Click the linked text to read the live update summary from that moment in court.]

Identifying Zimmerman’s voice

The jury heard five different witnesses identify Zimmerman as the voice heard screaming for help in the background of a 911 call made by a neighbor at the Retreat at Twin Lakes complex.

First to testify was Sandra Osterman, who is married to federal air marshal Mark Osterman. She identified Zimmerman as the voice heard in the call.

Next was her husband, Mark, was called back to the stand. He explained more about how he helped

Zimmerman get his concealed weapons permit, pick out a gun and exercise gun safety. He also identified Zimmerman as the person screaming for help in the 911 call.

A former co-worker, Geri Russo, also said it was Zimmerman’s voice she heard in the call.

Leanne Benjamin and John Donnelly, a married couple that supported Zimmerman after the shooting and worked with him on a political campaign before the shooting, also said it was his voice on the call.

Benjamin said she got to know Zimmerman while he worked next door to her real estate agency, helping customers she referred with insurance.

In cross examination, Prosecutor Bernie de la Rionda asked her about the expletives Zimmerman is heard saying in the non-emergency call.

She said she thought he was saying them as comments, and they didn’t seem like ill-will.

Donnelly testified to giving the defense a check for $2,500, donating $500 to the defense fund online, and then taking Zimmerman to buy suits for court.

He called Zimmerman a dear friend and said there was no doubt in his mind the voice in the 911 call belonged to Zimmerman.

The court heard Donnelly describe his experience as a medic in Vietnam, running to help wounded men, and how a man can sound different, but he would know who it was he was running toward to help.

Benjamin and Donnelly both told the jury they heard Zimmerman yelling while “Whooping it up” as they worked together on a political campaign.

Trayvon Martin’s father’s response

Investigators Doris Singleton and Chris Serino testified that Tracy Martin, Trayvon’s father, told them he didn’t recognize his son’s voice in the same call.

Serino said he played all of the 911 calls for the grieving father and after the one with screams for help and the sound of a gunshot, he asked him if he recognized the screams as Trayvon’s.

Martin was looking away from him, but said no under his breath, Serino said.

Singleton, who said she was about eight to ten feet away, described Martin as upset and crying as he listened to the recording.

“I can’t imagine having to go through that because I have children. I couldn’t imagine,” she said.

In his own words - Tracy Martin testifies

Tracy took the stand and told the jury his world turned upside down when he heard the shot that killed his son in that 911 call.

He described pushing back from Serino’s desk and shaking his head. He said he told Serino he wasn’t sure if it was his son’s voice, but never denied it.

The next time he heard the recording was at the Sanford mayor’s office, where he says he listened to it about 20 times and said he knew it was his son’s voice.

“Basically what I was listening to, I was listening to my son’s last cries for help. I was listening to his life being taken. I was trying to come to grips that Trayvon wasn’t here no more,” he said.

De la Rionda asked him why he played it over and over again.

“It wasn’t as much as I was trying to deal with it, I was just trying to figure out on the night of February 26, 2012, why did the defendant get out of his vehicle and chase my son?” Martin asked.

Audio line-ups

Former Sanford Police Department Chief of Police Bill Lee told the court he offered to be present when the 911 call was played for the Martin family at the mayor’s office, but was excluded.

He said it was better for something like an audio line-up to be done individually.

When questioned in cross examination, Lee confirmed a witness would be tainted if they said they heard audio on TV before they were asked to identify it because they would be influenced by the context they saw it in.

“Soft” and “not athletic”

Adam Pollock, who owns Kokopelli’s Gym and Fitness center, called Zimmerman “soft” and described him as “not athletic.”

He described and demonstrated with the help of O’Mara how a “ground and pound” maneuver works.

He said Zimmerman’s exercise regimen consisted of grappling classes and later boxing classes, though Zimmerman never got past learning how to punch on a punching bag.

Toxicology allowed as evidence

Judge Nelson ruled Martin’s toxicology report, which shows traces of THC in his system, will be allowed as evidence.

THC is the active ingredient of marijuana.

Defense attorney Don West argued the evidence should be admitted because it is a focus to the case of self-defense as Zimmerman described Martin as looking like he was on drugs to the dispatcher.

West said an expert till testify that the level found in Martin is sufficient to show impairment and is relevant for the jury to hear.

For the state, Guy argued the defense was trying to “backdoor negative character evidence.”

Judge Nelson told him the state would be able to cross examine the defense’s witness and offer their own rebuttal witnesses as she made her ruling.

Court will continue Tuesday at 8:30 a.m. so the court can consider the admission of an animation as evidence.