An 88-year-old man who was arrested shortly after the death of his ailing wife on suspicion of aiding in her suicide will not be charged with any crime.

San Diego prosecutors determined that the case against Alan Purdy couldn't be proven beyond a reasonable doubt, said Tanya Sierra, a spokeswoman for the district attorney, on Wednesday night.

Margaret Purdy, 84, was found dead in her home with a plastic bag over her head in March, her death ruled a suicide by the county medical examiner. Family said she had becoming increasingly depressed as she battled a series of ailments and injuries in her final years while her husband doted on her.

"She had mentioned for some time that she was under a great deal of pain and that this was a very hard life," the couple's son-in-law, John Muster, said in a telephone interview from Berkeley at the time of the arrest.

The once vibrant woman left a suicide note on her desk after being bedridden in her final years from severe pancreatitis, as well as an autoimmune disease, a crumbling spine and three fractured vertebrae that never healed, The Los Angeles Times reported.

Alan Purdy's sister-in-law, Margot Smith, told The Associated Press Wednesday that it would have been awful if prosecutors had decided to pursue a case. "I'm absolutely delighted to hear it. He's 88 years old and hard of hearing and he loved his wife dearly," Smith said.

Smith added that Alan Purdy was so hard of hearing that he had trouble making out what authorities were saying to him at the time of his arrest.

"I'm delighted to hear this," Purdy's daughter, Catherine Purdy, a Berkeley psychologist, told The Times. "I feel like justice has finally happened."

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