A nurse facing criminal charges in the rape of a woman who was incapacitated before later giving birth at a long-term care facility in Phoenix pleaded not guilty Tuesday.

The only comments by Nathan Sutherland came when he identified himself to the court and stated his birthdate. Afterward, Sutherland’s attorney vowed a vigorous defense, but declined to answer questions from reporters.

Authorities say Sutherland, 36, was working at a licensed practical nurse at Hacienda Healthcare in Phoenix when he allegedly raped the 29-year-old victim, who has been in long-term care since age 3 after suffering a near-drowning.

She gave birth to a boy at the facility on Dec. 29. Employees said they had no idea she was pregnant.

The surprise birth triggered reviews by state agencies, highlighted safety concerns for patients who are severely disabled or incapacitated and prompted the resignations of Hacienda’s chief executive and one of the victim’s doctors.

Investigators say Sutherland’s DNA matched a sample from the woman’s newborn boy, who is being cared for by her family.

Sutherland, who was shackled and carrying a legal pad during the arraignment hearing, pleaded not guilty to charges of sexual abuse and abuse of a vulnerable adult. He remains jailed on a $500,000 bond.

Hacienda fired Sutherland after his arrest. He has since given up his nursing license.

Sutherland’s attorney David Gregan said he’ll make sure his client’s constitutional rights are respected. “Mr. Sutherland, just as you and I are, is entitled to a full defense,” Gregan said.

Gregan, who had previously said there is no direct evidence linking Sutherland to the crime, declined to comment on the DNA Evidence prosecutors say they used to arrest his client.