Prosecutors say Kenneth Jackson and Alice Waterman burned more than 100 acres and destroyed one home in the Coarsegold area last year.
Attorneys say the jury has already heard 32 mini trials -- one for each of the fires in this case. On Monday, the defense called an expert to raise questions about Cal Fire's investigation.
Kenneth Jackson and Alice Waterman sat quietly through hours of testimony in their arson trial. The defendants have been coming to this courtroom for hearings since last year. Jury selection started in December, and opening statements were back in January.
"The length alone is completely abnormal; I've never been in a trial anywhere near this length," said defense attorney Martin Jones.
Jones says the format is also unusual because the judge felt it was best to present evidence for each count separately.
"They broke it up into like a mini trial for each separate fire, so there are 32 fires," said Jones.
Jackson and Waterman are accused of setting those fires in the Yosemite Lakes Park area of Coarsegold in May and June of 2013. Investigators believe at least 10 of them started on the couple's own property. Prosecutors have said a combination of video cameras, live surveillance, witness reports, and GPS data ties the couple to the crimes.
But defense attorneys have argued there's no solid proof. On Monday, they called the owner of a fire investigation company to the stand to testify that Cal Fire left too many questions unanswered. But the real question may be how jurors are handling the abundance of information.
"Losing interest or just having too much information, it's difficult, and I can imagine it's difficult for the jury as well," said Jones.
Attorneys are hoping the trial will wrap up in the next couple of weeks. Then it will be up to the jury to sort through months of evidence and try to reach a verdict.