CONROE, Texas -

A Montgomery County judge ruled Thursday the man accused of setting Robert Ray Middleton on fire in June 1998 can stand trial as an adult, even though Don Willburn Collins, now 28, was 13 at the time of the attack.

"I do see the light at the end of the tunnel," said Middleton's mother, Colleen, after the judge's ruling. "Hopefully one of these days it will end."

The four-day hearing saw more than 20 witnesses called to the stand, many of whom testified they heard Collins admitting he tied Middleton, who was 8 years old at the time, to a tree and set him on fire. However, it was Middleton's own videotaped deposition that seemed to have particular impact on the judge. Shortly before his death in 2011, Middleton formally accused Collins of sexually molesting him, dousing him with gasoline and setting him on fire near his Splendora home.

"After almost 13 years this child was able to communicate new information," Judge Kathleen Hamilton said form the bench. "He told that Don Collins burned him and more than this, in May of 2011, he told that Don Collins sexually assaulted him. I find this child's testimony during the video deposition to be credible and to be true."

"We're ecstatic that she looked at Robert's deposition and said that she believed that it was credible and true," said Colleen Middleton. "He did that deposition, he knew he was dying and I'm glad it wasn't for nothing."

Detectives also said it was Middleton's statement that allowed them to kick-start an investigation that had gone cold. Montgomery County Attorney J.D. Lambright said investigators also compiled 60,000 documents and interviewed more than 60 witnesses as part of the case against Collins, who did not testify on his own behalf during the hearing.

"I tell you this is a tremendous victory," Lambright said after the hearing.

Even though Middleton did not die until 2011, his death was ruled a homicide because a medical examiner concluded he died from a specific type of cancer caused by the catastrophic burns covering 99 percent of his body. Prosecutors said this is why they sought murder charges. However, Collins' attorneys argue the entire case is circumstantial.

"There is no physical evidence that links Don Collins to this case," said defense attorney E. Tay Bond. "There are no eyewitnesses and essentially every shred of evidence they have is merely hearsay."

Bond also argued that Collins should not have been certified as an adult because at the time Middleton was attacked Texas law prohibited children under the age of 14 from standing trial in adult court. Prosecutors argue that since Middleton did not die until 2011 that point is moot.

Collins is expected to go to trial later this year. Collins is also facing a separate charge in San Jacinto County for failing to register as a sex offender; the third time he has been charged with this crime.

Collins was convicted of sexually assaulting another 8-year-old boy two years after the attack on Middleton.