After he was accused of molesting his young special needs son, Jose Cordero spent 35 days in a Miami jail and was barred from seeing his family for months.

The allegations did not come directly from the 7-year-old boy, who has autism, speaks little and cannot write on his own. Instead, they came from the child's elementary school teacher who claimed he relied on a technique called "hand over hand," guiding the boy's hands with his own to write down the disturbing details of sexual abuse.

This form of "facilitated" communication is a science that has been largely debunked in the wake of high-profile scandals involving wrongfully accused parents over the past couple decades.

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That didn't stop Hialeah police from arresting Cordero in October. But Miami-Dade prosecutors soon grew suspicious of the teacher's story.

The boy, working through the teacher with the same technique, later made even more outlandish claims, using words and phrases familiar to adults but not to young children. And when paired with another teacher and specialists, the boy could no longer write a single word, let alone repeat detailed accusations about molestation.

Weeks after the initial arrest in October, prosecutors rushed to get Cordero out of jail while they awaited results of DNA testing. On Wednesday, after those tests came back negative, the Miami-Dade State Attorney's Office officially dropped the sexual battery case against Cordero.

"Due to significant inconsistencies within the victim's disclosures coupled with controversial means by which the disclosure was obtained, and a lack of corroborating witnesses, the state would be unable to prove this case beyond a reasonable doubt at this time," according to a final State Attorney's report released Wednesday.

The conclusion of the case now raises questions whether the Hialeah elementary special-education teacher, Saul Fumero, made up the allegations — and whether the Miami-Dade school district knew he was using a largely discredited method of communication with the autistic child.

A Miami-Dade Schools spokeswoman did not say whether the district would review Fumero's actions, but noted that teachers are required by law to immediately report allegations of abuse.

The spokeswoman, Daisy Gonzalez-Diego, added that the district "does not endorse the facilitated communication method and does not provide training" for it because it is not accepted by those working in the field of "augmentative and alternative communication."

Fumero, 32, who has been with the school district for four years, acknowledged to police that he had no formal training in "facilitated communication." Reached by text, Fumero, who lives in Hialeah, declined to answer questions from the Miami Herald, citing pending litigation. The allegations of abuse must still be hashed out before a judge in Miami-Dade's dependency court.

James Todd, a psychology professor at Eastern Michigan University who has studied facilitated communication, reviewed the State Attorney's final report and said the school district still bears responsibility.

"The bottom line is that that school let a teacher use a technique that was never credible and was already scientifically discredited in the early 1990s," said Todd, who has worked as an expert for people falsely accused in similar cases.

Cordero, 50, was not in court Wednesday and could not be reached for comment. Prosecutors never formally charged him with any crime. His lawyer could not be reached for comment. His wife, reached at their home in Hialeah, said she is grateful the case had concluded but she has not spoken with her husband since his arrest.

The technique of facilitated communication involves a "facilitator" holding a special needs person's hands or arms while they type on a keyboard or write or point to letters. The method became popular in the early 1990s. "We thought it was a ridiculous fad that would run its course," Todd said. "The obviousness of the facilitator control made us wonder, 'Who could be fooled by this?'"

But some people believed in it.

And soon, dozens of facilitators across the country began claiming their autistic or intellectually disabled students were detailing abuse. But in case after case, questions arose about whether the facilitators were unconsciously — or even maliciously — doing the communication themselves.

One of the most notorious cases was that of Betsy Wheaton, a 16-year-old girl with autism who could not speak. In 1992, her parents were arrested after their daughter's facilitator — trained in the technique at the University of Maryland — alleged the girl was being abused at home. The case was later dropped when researchers concluded facilitator Janice Boynton was wrong; Boynton has gone on to disavow the method.

Researchers and critics deemed facilitated communication nothing more than junk science preying on the hopes of parents who long to communicate with their non-verbal children. Even the American Psychological Association, in 1994, declared there was "no scientifically demonstrated support for its efficacy."

"There's not one study in 25 years that holds up to scientific scrutiny that shows that this is a viable means of communication," said Dr. Howard Shane, an associate professor at Harvard Medical School who served as a defense witness in the Wheaton case.

Still, variations of facilitated communication enjoy support in some circles. Christine Ashby, the director of the Institute on Communication and Inclusion at Syracuse University, said facilitators are taught to provide stability while the other person is typing but to resist movements to avoid guiding their hands. She said some research supports the method.

"There are a large number of individuals who once required support to communicate and now type independently, read aloud what they type, have now graduated college," she said. "I think there are a lot of folks where there's well-documented evidence of success."

Still, cases of wrongfully accused parents have persisted.

In 2007, a Michigan father spent 80 days in jail after a teacher's aide claimed his 14-year-old daughter had typed out allegations of rape. The case was later dropped. Two years ago, the family was awarded nearly $6 million in lawsuits for false arrest.

In addition to Miami-Dade, three of the largest school districts in Florida — Broward, Palm Beach and Orange counties — told the Miami Herald they do not use the technique.

"Essentially, we and experts in the field believe that the facilitator is 'writing' the message and not the student/user," Kevin McCormick, director of the Palm Beach County school district's special education department, said in an email.

In the Hialeah case, police were called to James H. Bright / J. W. Johnson Elementary School in October.

Special education teacher Fumero, who had been working with the student for two years, claimed the boy was keeping a diary using "hand over hand technique." With Fumero's "assistance," the boy wrote that his dad was touching his private parts and "wrote that his dad needed help, but was scared to go to jail," according to a Hialeah police arrest report.

Hialeah Detective Alexander Dorado began asking the boy questions. With Fumero's help, the boy wrote detailed allegations for him. "I'm very serious," the boy supposedly wrote, according to the report.

But it wasn't only police. The University of Miami's Child Protection Team, which works closely with police and prosecutors, also interviewed the child — again, with Fumero's assistance. The boy was even more detailed, saying he recalled "seeing blood and semen and mentioned 'baby making juices.' "

When police came knocking, the family was shocked, according to the State Attorney's report. The boy's mother almost fainted and "appeared completely unaware of any abuse." Cordero appeared "very concerned about his son and whether he was safe" — and "adamantly denied the allegations," the state's report said.

Four days after the initial disclosure and Cordero's arrest, the school called Hialeah police to say the boy had made a second disclosure working with the teacher. This time, the allegations included sophisticated phrases beyond the vocabulary of most children of 7.

Through Fumero, he also accused the mother of abuse: "I am playing with my life and it's not a fun game. I should have told you how evil she is she has schizophrenia and doesn't take her medicine like she's supposed to." The victim wrote that the older sister had also "been conditioned to be a sex slave." The boy allegedly wrote: "This is all a very ugly and disturbing horror story but all true!"

Hialeah detectives spoke to the boy's sister, who was shocked by the new allegation and "unwaveringly denied knowing of any abuse, being abused, or abusing the victim herself."

The investigation turned to Fumero, who admitted that he "had not had any formal or professional training in the technique." And the school's principal later told police that "she had reservations regarding the disclosure" and had moved the boy out of Fumero's class.

Prosecutors soon learned the boy could not write with his new teacher or anyone else at the school. Even a therapist at Kristi House, the nonprofit that works with prosecutors on sexual abuse cases, said she "had not seen anything that indicates to her that the victim is capable of writing pages of information through the 'hand over hand' technique.

"To date, the victim has only written with Mr. Fumero," prosecutor Laura Cespedes wrote in her final report.