Police arrested John Sandoval, 45, just after 8 a.m. Thursday at his home in Las Vegas.
Tina Sandoval, 24, disappeared after police say she visited the home of her estranged husband, John Sandoval in October 1995 to supposedly settle a debt.
She has not been seen since.
According to the arrest affidavit filed in the case, officers staked out John Sandoval's house in 1995after Tina Sandoval disappeared and caught him climbing out a window with fresh scratches on his neck and upper chest.
In the arrest affidavit, detectives say the scratches appeared consistent with wounds caused by fingernails and a struggle.
Officers saw a shovel still wet with mud, a white five-gallon bucket inside John Sandoval's car, nylon rope with a loop tied at the end consistent with a lasso or noose and a 9mm semi-automatic handgun, according to the affidavit.
Police arrested John Sandoval for an unrelated criminal trespass investigation, according to the affidavit. During questioning, detectives say John Sandoval would not allow them to collect evidence from the scratches.
"Whenever the defendant was left unattended he would continue cleaning and biting his fingernails off," the affidavit says.
Detectives later searched John Sandoval's home and found men's brown work boots that were wet and appeared to have been washed off, detectives wrote.
Weld County District Attorney Ken Buck says big new evidence hasn't surfaced in the time since the disappearance, but he felt charges should be brought.
"I looked at the case now and decided it should be filed. It was my decision," Buck told 9Wants to Know Thursday. "There's no new DNA evidence, no smoking gun, the body hasn't been found."
He says with the passing years, it becomes harder for anyone to claim Tina Sandoval just left on her own.
"The defense, at the time when a body isn't found, is that the victim left town and didn't tell anybody. As time goes on, that defense is less plausible," Buck said.
"It's more appropriate now than it was before to bring this case," he said.
"We are pleased that the Greeley Police Department and the Weld County District Attorney's Office have moved ahead with the arrest and prosecution of John Sandoval," wrote Michael and Mary Ellen Torunai, Tina's parents, in an e-mail to 9Wants to Know.
"We have long held out hope that [Tina's] remains would be located, but at this point in time, this does not seem likely. We support the decision to move ahead and prosecute John Sandoval without having the closure of knowing where our daughter's remains are located," the Tournai family wrote.
John Sandoval has a history of harassing and stalking other women, according to previous 9NEWS reports. Click hereto view the arrest warrant.
You can contact investigative reporter Jace Larson at jace.larson@9news.com, 303-871-1432 or http://twitter.com/jacelarson./>