A 21-year-old man with Asperger’s syndrome pleaded not guilty Tuesday in Circuit Court in connection with the death of his 19-year-old autistic girlfriend in Wahiawa.

Kaniala K. Avilla-Rapoza appeared before Judge Colette Garibaldi at his arraignment via closed-­circuit video link from the Oahu Community Correctional Center after an Oahu grand jury indicted him with second-degree murder in Nelibeth Albert’s death.

Attorney Moani Crowell pleaded not guilty to the murder charge on Avilla-­Rapoza’s behalf.

Garibaldi confirmed his bail at $500,000 and set his trial for July.

According to a court document, police said Avilla-­Rapoza admitted he killed Albert by choking her. He led police down a trail at the Wahiawa Freshwater State Recreation Area to Albert’s body May 18.

Avilla-Rapoza and Albert had been dating for two months but had known each other since they were classmates at Leilehua High School.

Individuals with Asper­ger’s syndrome have impaired social and communication skills.

Crowell said they contest the validity of Avilla-Rapoza’s statement to police. When you have someone who has special needs such as Avilla-Rapoza, “there’s an inability to comprehend and intelligently waive your legal rights.”

“He insists on his innocence,” Crowell said after the arraignment.