Navy sailor Randall J. Tilton faces up to 210 years in prison after pleading guilty Monday in U.S. District Court in New Haven to what investigators say is one of the worst cases of sexual abuse of young children, two of whom were just 4 and 6 months old when he began to violate them.

The 31-year-old New Hampshire native, a Machinists Mate 1st Class stationed since 2016 at the Naval Submarine Base in Groton aboard the USS South Dakota, is also accused of producing pornographic images of his victims that were distributed via the internet and dark web. He faces 15 to 210 years in prison, lifetime supervised release and registration as a sexual offender, and hefty fines and restitution orders that have yet to be calculated. He pleaded guilty to seven counts of production of child pornography, each of which carries a mandatory minimum sentence of 15 years in prison.

The crimes took place in Connecticut, California and New Hampshire, according to testimony, and at times Tilton restrained the children while performing and recording the sadistic and masochistic acts.

The government has dozens of videos and still images to prove its case against Tilton, though he attempted to discard his phone between two frames of the bilge of a Navy ship when he learned in October 2019 that the Groton Town Police wanted to speak with him. The phone was recovered by Navy investigators, and other electronic equipment, including laptops and flash drives, were seized. The government also has incriminating letters that Tilton wrote while incarcerated at the MacDougall-Walker Correctional Institution.

U.S. District Judge Jeffrey A. Meyer explained the complicated plea agreement in minute detail to Tilton, who wore a neon orange prison jumpsuit and face mask in the courtroom, and after nearly two hours of review, he said "I do" to admit his guilt. Meyer said the victims, or their parents, would have the opportunity to submit impact statements or testify at the sentencing hearing scheduled for March 1, 2021, and that Tilton would have the opportunity to "explain in some ways what is the inexplicable."

Some of the crimes involved babies and young children who were in Tilton's care and custody and took place over a number of years, according to Assistant U.S. Attorney Nancy Gifford. All involved children were under 12 years old.

Other crimes involved children he preyed upon quickly when given the opportunity. Invited to a barbecue in Connecticut in June 2019, Tilton lured a 7-year old girl into the garage, had her lie on the cement floor with her pants and underwear down and took still images of her, Gifford said.

The wide-ranging investigation by Groton Town Police, the Naval Criminal Investigative Service and FBI began in late October 2019 when the parent of an 8-year-old girl identified only as "Minor Victim One" disclosed she had been sexually abused for years by Tilton, who recorded some of the abuse.

During a recorded interview with Groton Town Police, Tilton confessed he had sexually abused the child from the age of 6 months old and had engaged in similar behavior with four or five other victims. During that interview, he also admitted that when he learned police wanted to speak with him, he attempted to dispose of the phone.

The government obtained 35 videos and 66 still images depicting multiple types of sexual assault, some of which displayed "masochistic abuse to include her restraint," in Connecticut and New Hampshire, according to Gifford. Tilton sexually abused the child throughout her life, recording the abuse in some instances, and showed her pornographic images involving other children.

Gifford went on to describe six other offenses. Minor Victim 2 involved a child who was born in 2018 and was assaulted beginning when she was approximately 4 months old. Minor Victim 3 involved the 7-year-old child at the barbecue in Connecticut. Minor Victim 4 involved a 4-year-old who was victimized in February 2016. Minor Victim five involved a 3-year-old who was assaulted in May 2015 in California. Minor victim 6, also abused in California, was 3 years old. Minor Victim 7, born in 2011, was abused over a five-year period beginning in 2014.

Had the case gone to trial, the government would have had to prove that Tilton persuaded, induced or coerced the victims to take part in sexually explicit conduct for the purposes of producing visuals of the sexual conduct and that he transmitted them using materials made or produced by interstate conduct.

Tilton's calculated offense level, under federal sentencing guidelines, is higher than the highest offense level, and could involve a 210-year prison sentence, which the judge pointed out is well beyond the normal lifespan.

The government intends to argue for the full 210-year sentence, while Tilton and his attorney, Moira Buckley, will have an opportunity to argue for a sentence as low as 15 years.

Judge Meyer said he would be imposing a just punishment that takes into account the seriousness of the charges, promotes respect for the law and deters Tilton and others who might be tempted to engage in this type of crime. The judge said he also has to think about Tilton's potential for rehabilitation, telling him, "You can never go back, ever, in indulging this kind of abuse or exploitation of children."

In addition to the federal charges, Tilton is also facing charges in state Superior Court. Records of that case have remained sealed while the federal investigation took place.

k.florin@theday.com