Depending on which attorney the jury believes, the case against Bulos "Paul" Zumot is either a clear example of a toxic relationship reaching a deadly conclusion or a misguided attempt to lock up an innocent Palo Alto man based on shifty evidence.

After hearing both closing arguments Tuesday in a San Jose courtroom, the jury in Zumot's arson-and-murder trial prepared to deliberate Wednesday on whether Zumot had been wrongly charged or whether he had killed his girlfriend, Palo Alto real-estate agent Jennifer Schipsi, and then burned down their Addison Avenue cottage to hide the evidence.

On Tuesday, the jury heard Deputy District Attorney Charles Gillingham and defense attorney Mark Geragos wrap up their respective cases and ask them to return with what each characterized as the only reasonable verdict. They also heard the two attorneys summarize, in strikingly different terms, the evidence that was presented over the month-long trial.

"This is no longer a whodunit -- it never was," Gillingham said early in his closing argument, before going on to summarize the evidence from cell phones, witnesses and surveillance videos that the jury saw.

Gillingham said Zumot, 37, was the only person who had the motive, the opportunity and the desire to kill Schipsi, 29. He pointed to their two-year history of domestic disputes -- disputes that led both Zumot and Schipsi to file police complaints against one another. He also emphasized the long strings of insulting text messages Schipsi sent Zumot early in the morning of Oct. 15, 2009 -- messages in which she threatened to go to the police if he didn't pay her the money she claimed he owed her.

Gillingham argued that Zumot strangled Schipsi that day and later dowsed the house with gasoline and turned on the burner on the stove in hopes of causing an explosion that would hide his crime. There were no signs of a forced entry into the home nor of a burglary, Gillingham said, and no one disputed the coroner's finding that Schipsi was murdered before the fire occurred.

He argued that these pieces of evidence -- as well as text messages, records from cell towers and witness testimony -- all point to the fact that Schipsi's death resulted from a "personal killing." He reminded the jury that Zumot and Schipsi had a fight over an 18-hour period before her death and said Zumot knew she was at the house by herself that day -- knowledge that enabled him to plan the murder.

"Last thing she probably saw was the person with whom she lived strangling her," Gillingham told the jury.

Gillingham told the jury that Zumot was with Schipsi all day and had "absolutely no alibi" for Oct. 15, 2009. No one who could vouch that they saw Zumot until that evening, he said.

Once Zumot got to the fire, he made a long string of phone calls and sent various texts, but he only tried to reach Schipsi twice during the two-hour span -- a behavior that Gillingham characterized as unusual for a man who typically exchanged dozens of messages with Schipsi over the course of a day.

"His silence is damning. His silence is deafening," Gillingham told the jury. "His silence yells louder than anything he could've said at the witness stand: 'I murdered Jennifer.'"

But Geragos dismissed the prosecution's evidence as "a lot of nonsense" that the prosecution put in front of the jury "in the guise of evidence." Geragos, whose previous clients included Michael Jackson and Scott Peterson, argued that Palo Alto police, rather than investigating who committed the murder, decided on the day of the fire that Zumot was the killer and focused its resources on building a case against him.

"They had a theory, and they weren't going to be bothered with the evidence," Geragos said.

He told the jury that the prosecution's theory about Zumot taking Schipsi's phone and traveling with both phones on the day of the fire didn't stand up to evidence. He also derided the testimony of Jim Cook, the prosecution's cell-phone expert who used data from AT&T cell-phone towers to map out the locations of Zumot's and Schipsi's iPhones on the day of Oct. 15, 2009.

During his cross-examination of Cook, Geragos showed numerous instances in which the records seemed to suggest that a person could be using a tower in Hawaii and California within minutes of each other and argued that the phone company "merged" the data, making it impossible to figure out who is making the call and who is receiving it. Gillingham later countered in his rebuttal that in most cases, the phone calls Cook mapped were corroborated by other phone records, as well as videos and witness testimony.

Geragos also pointed to a lab report from the Bureau of Alcohol, Tobacco, Firearms and Explosives, which examined Zumot's clothing and did not find any evidence of accelerant on his sweatshirt, pants or socks. This finding contrasted with that of Rosie, an accelerant-sniffing dog used by arson investigators after the fire.

Geragos recalled testimony from a Palo Alto police officer who testified that Zumot did not have any scratch marks or bruises on Oct. 15, 2009. The fact that there "wasn't a single mark" on Zumot suggests that he did not get into a fight with Schipsi that day, Geragos argued.

He also criticized Palo Alto police for not investigating Hisham Ghanma, a person against whom Schipsi and Zumot had both filed a restraining order shortly before the fire, and for not following up on a statement made by Zumot's landlord, John Eckland, who testified that he saw a dirty white sedan parked close to the house on the day of the fire.

"They didn't show you any evidence linking Bulos to the crime," Geragos told the jury.

The prosecution, Geragos maintained, focused much of its case on "character assassination." He said that the long and heated string of messages exchanged between Zumot and Schipsi on the day of the fire consisted of insults and threats that she was sending him -- not the other way around. The only major actions Zumot had taken against Schipsi over their relationships occurred in 2008, when he kicked her car and spat at her. She filed a police report, and Zumot pleaded guilty to sending her harassing text messages. He was put on probation and forced to take domestic-violence classes in San Jose.

"This guy has learned over a year ago that he couldn't do those kinds of things," Geragos said, pointing at Zumot.

While Gillingham cited statements from several witnesses who said over the course of the trial that Zumot had threatened to kill Schipsi and set fire to his house and his business, Geragos disputed this testimony. He said it's possible that Schipsi was lying when she told all these people that Zumot threatened her.

In his rebuttal, Gillingham defended the Palo Alto police and said officers were simply following the evidence, all of which was leading toward Zumot. He also talked about all the messages that were deleted from Schipsi's iPhone, many of which related to her dispute with Zumot. He suggested that Zumot deleted most of the messages on both his and her phones as a way to cover up the crime.

"Is it a coincidence that Jennifer's phone has nothing on it?" Gillingham asked.

He compared the defense to an octopus that, having no real weapons, shoots out ink into the water and attempts to escape into the darkness.

"Time to clear the air and to clear the water because the defendant is guilty as sin," Gillingham said during his rebuttal.

The jury is scheduled to receive its instructions from Judge David Cena Wednesday morning. It will then begin its deliberations.

Related stories:

■ Zumot concludes testimony in his own murder trial

■ Zumot grilled over turbulent relationship with Schipsi

■ Zumot breaks down on stand: 'I still love her'

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