Facing criminal accusations in two counties,
Cain's hands were cuffed and chained to his waist during the brief hearing in a Rancho Cucamonga courtroom and he fidgeted as his attorney first spoke to the judge. The police officer, who wore a dark green jail uniform, nodded and smiled at his attorney as the hearing ended and a bailiff escorted him out of the room.
His attorney, Andrew Pongracz, declined to comment after the hearing. Cain is due back in court in connection with the weapons charges next month.
San Bernardino County prosecutors charged Cain this week with 10 felony counts, including multiple counts of possessing assault weapons. Authorities found the guns — part of an arsenal of more than 100 weapons — when they searched Cain's Rancho Cucamonga home after the 31-year-old officer was arrested on suspicion of having unlawful sex with a 15-year-old LAPD cadet.
The accusations against Cain surfaced as Los Angeles police began investigating a string of thefts allegedly carried out by a group of teenagers in the department's cadet program, its signature youth initiative. Seven cadets have been arrested.
Police believe the cadets took police cars and other equipment, including radios, Tasers and a bulletproof vest. The cadets allegedly stopped at least one motorist while driving the stolen vehicles, giving the driver a warning, police said.
Text messages indicate Cain was aware of the thefts, Los Angeles Police Chief Charlie Beck said after he personally handcuffed Cain last month. Cain worked in the equipment room of the department's 77th Street station, where all but one of the arrested cadets were assigned. He was not assigned to youth programs, Beck said.
A spokesman for the Los Angeles County District Attorney's Office said Friday that prosecutors there are still reviewing the case against Cain and have not charged him in connection with the unlawful sex accusation. He is scheduled to appear in a Los Angeles courtroom next week.
Before his latest arrest, the LAPD had ordered Cain to stay at home and away from work.
The scandal unraveled in June, police say, when some of the cadets were caught driving two of the stolen police cars, leading officers on a chase that ended with two separate crashes.
3:14 p.m.: This story was updated to include Robert Cain's current status with the LAPD.