SAN DIEGO — A Camp Pendleton Marine accused of having sex with a missing 14-year-old girl found in his barracks believed she was in her early 20s, his defense attorneys argued Thursday.

An attorney for Pfc. Avery Rosario said during a brief preliminary hearing in a military courtroom at Camp Pendleton that the Marine met the girl on Tinder, a dating app for adults, where her profile said she was 21 years old.

The argument by the defense capped a brief hearing in which no witnesses were called, and much of the evidence — which includes conversations on Tinder and Instagram — was not shown. The evidence was filed directly with the Marine colonel tasked with recommending whether Rosario should face court-martial for allegations of sex with a minor.

No decision was made Thursday. The prosecution and defense will each file further arguments in writing, with the last due Aug. 25.

Rosario is charged with three counts of sexual assault and two charges of violating liberty restrictions — leaving base without permission — according to charges base officials released Tuesday. The charges indicate the alleged crimes or violations happened June 27.

The next day, military police at Camp Pendleton found the girl in a barracks. The military notified the county Sheriff's Department, and the girl was reunited with her family.

According to the Sheriff's Department, the teen's grandmother said the girl ran away from home June 9. She had run away on previous occasions, but quickly returned. With the teen still unaccounted for on June 13, the grandmother reported her missing.

The story of the missing girl turning up on the base drew public attention when the girl's aunt posted a TikTok video alleging the girl had been trafficked.

Thursday's hearing did not give much insight into the prosecution's case. The prosecutor did not give a closing argument during the hearing, opting to instead handle it all in writing.

But one of Rosario's defense attorneys gave a closing argument in the small courtroom, where several news reporters were present.

Defense attorney Capt. Katherine Malcolm said her client had "a genuine belief that the woman he met on Tinder apps was 21 years old." Malcolm said the girl's profile stated, "I know I look young, but hey when I'm 30, I'll look like I'm in my 20s."

Malcolm said friends of Rosario told investigators they were under the impression that the woman was in her early 20s. At least one of them said the girl told him she was 22.

The defense attorney said the girl initiated the Tinder conversations with Rosario on June 26, and she also suggested they move their conversation over to Instagram.

Malcolm said the girl's credibility is at issue. She said the girl told investigators she spent the night in a closet in the barracks, but Rosario's roommate said he found Rosario gone and the girl asleep in bed, snoring with the television on, Malcolm said.

The roommate kicked her out. She called Rosario, who returned from a work gathering and let her back into the room.

According to the defense, the girl told investigators she had been trafficked by a man named Hector for the last year, and said Hector was "pulling the strings." She said her "whole plan" was to get caught while on base, and that when she was found she would be finally safe.

Malcolm said the girl's actions "were not the actions of somebody looking to be rescued."

Evidence filed by prosecutors includes the girl's Tinder profile and conversations she and the Marine had on the app. Defense evidence included direct messages between their client and the girl.

The Naval Criminal Investigative Service questioned Rosario right after the girl was found, then released him to his command pending charges. Rosario is with Combat Logistics Battalion 5, 1st Marine Logistics Group.

Rosario was taken into custody Aug. 1. He remained in custody Thursday.

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