As a result, many of those who prey on society's most vulnerable walk free or get probation.
That's what happened in the case of Dwayne Young, 58, charged in September 2012 with kidnapping the 65-year-old Richardson for his Social Security benefits.
After kidnapping Richardson, Young allegedly took him to his Southwest Philadelphia home where he punched the diminutive 5-foot-1, 120-pound man, pushed him down stairs and locked him in the basement for almost five months in 2012. Young typically fed Richardson just one frozen dinner a day, authorities said.
Assistant District Attorney Noel Ann DeSantis was determined to prosecute Young, knowing this would be the toughest case in her 13 years on the job.
Young "thought he found the perfect victim and that he could get away with it," DeSantis said. "How would anyone ever hear what Willie had to say because Willie can't communicate in the world?"
DeSantis, detectives and a four-person interpretation team spent about 60 hours over several months to get Richardson to a point that he could be understood in court. They created poster boards with photos to help him explain what he had endured.
Young, who knew Richardson through a family friend, kidnapped Richardson off the street one afternoon in April 2012, DeSantis said.
Young took him to the house where he lived, on Wheeler Street near 56th, and forced him into the basement, which locked from the outside.
When Richardson pounded on the door to get out, Young beat him, DeSantis said.
Young allowed Richardson upstairs only when he left the house, but there was no escape.
"The phone line was cut . . . There were blinds everywhere. There were bars on the windows," DeSantis said.
Young coerced Richardson into giving him the PIN number to his access card to withdraw his $648 monthly Social Security disability checks.
Richardson's brother, Robert, now 61, was worried after he vanished and figured that Young might know his whereabouts. But when he knocked on the door, Young told him his brother wasn't there.
But Robert didn't believe him and repeatedly told police that he believed Young had his brother.
"Even if [the cops] did a walk through of the house, [Willie] wouldn't have heard them to yell," DeSantis said.
Five months after Richardson was kidnapped, police got a search warrant, broke into the house and rescued him.
Young returned home that night to find the search warrant posted on his door and Richardson gone. He immediately drove to South Detectives, demanding to see Richardson.
"The defendant was brazen," DeSantis said, he came looking for what he saw as his property.
"He wanted that money to buy crack," she said.
Police charged Young with theft by deception, unlawful restraint, terroristic threats, simple assault and false imprisonment.
Language specialists who evaluated Richardson said he has "difficulty telling his story sequentially in a connected way." His testimony, they said, would "not be easy or brief."
DeSantis had a difficult decision to make.
She could put Richardson through an arduous three-week trial and hope a jury believed him. If Young were convicted of kidnapping, he would face a maximum of 20 years behind bars, DeSantis said.
Or she could get Young to plead guilty to violating his parole in exchange for a 2 1/2- to five-year sentence. At the time of his arrest, Young was on probation for endangering the welfare of a child.
DeSantis chose to spare Richardson the courtroom anguish.
"I really felt it was abusive and to put him through that with a three-week trial would be mentally exhausting for him . . . Willie's level of justice is different than mine," she said.
So in the end, she said, "Justice was measured but not denied."
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