OAKLAND -- Moses Kamin admitted during a police interrogation that he choked his parents to death, but the legality of the 15-year-old's confession was challenged Wednesday by a defense attorney who wondered whether the teenager understood his rights.

While there is no question about whether two police interrogators read Kamin his Miranda rights just before questioning him, assistant public defender Drew Steckler pointed out, through questioning of the lead interrogator in the case, that his client might not have had the experience or knowledge necessary to understand what those rights meant.

Steckler is attempting to get the videotaped interrogation of Kamin thrown from the case, based on a legal argument that his teenage client did not understand he had the right to remain silent or have an attorney present during questioning.

In doing so, Steckler has focused on the age of his client, the teenager's past troubled life and the tactics various police officers used during the almost 12 hours Kamin was locked in a small, windowless interview room before he made his confession.

Kamin, now 16, is accused of killing his parents, Richard Kamin, 54, and Susan Poff, 50, by strangling both using a choke hold he learned at karate school. During the police interrogation, Kamin admitted he killed the couple, who adopted him when he was about 6 years old, because he had just been suspended from school for smoking marijuana and did not want to

Kamin also told police, after his confession, that he has had issues with anger management ever since he was "little," and spoke of the time before he was placed in foster care and eventually adopted by the parents he killed when he was physically and emotionally abused.

Kamin said he remembered that when he was 4 years old, he was locked in a dark room for three days without food, only finding a bathroom after he located a light switch. He also spoke about having food taken from him as punishment and about how one day he found frozen Eggo waffles in the freezer and ate them because he was so hungry.

With those statements as a backdrop, Steckler questioned Officer Eriberto Perez-Angeles, the lead interrogator in the case, about the conditions in which Kamin was left for almost 12 hours before he was questioned.

Steckler questioned the officer about how he and others frequently checked in on Kamin, trying to building a rapport with the teenager before reading him his rights and beginning questioning.

Stecker's questions focused on how officers put on an appearance of friendliness toward Kamin and about how those contacts could have confused the teenager about what rights he had.

Perez-Angeles admitted that he attempted to calm Kamin by being nice to him and frequently made physical contact with him in hopes of easing Kamin's worries and getting him to confess. That contact included frequently touches on Kamin's forearm and, at times, endearing shoulder pats.

"I promise you, you will feel better after you tell us. We can do this together," Perez-Angeles said at one point during the interview.

Alameda County Superior Court Judge Morris Jacobson will decide next week whether Kamin understood his rights and whether a prosecutor has presented enough evidence to put him on trial before a jury on charges of murder.