In a brief hearing in federal court in Greenbelt, Maryland, U.S. Magistrate Charles B. Day asked Nuss if he understood the case against him.
"I'm not totally involved in it, is what I'm saying," Nuss said.
Federal public defender Daniel Stiller said after the hearing that Nuss believes he is not totally responsible for bringing the children from Pennsylvania to the Maryland suburbs of Washington and that there was a "set up." Stiller refused to elaborate.
"It's a sad case, not a sinister one," Stiller said.
Nuss had an animated conversation with Stiller in the courtroom for about 20 minutes before the hearing began.
"He has acknowledged that his conduct was wrong," Stiller said.
When Day asked Nuss whether he suffers from mental illness, Nuss replied, "No sir, I'm not insane."
None of the children was hurt during the six-hour trip, but some of the students said they were afraid Nuss was going to kill them, according to an FBI affidavit.
"One of the students, fearing what was going to happen, wrote 911 in reverse on a fogged bus window," according to the affidavit from FBI special agent Thomas D. Neeson.
Students who were interviewed by the FBI said they saw the rifle behind Nuss and he told them not to go near it.
Children also told FBI agents that during the trip, a bus dispatcher tried to reach Nuss, but the driver ignored the calls.
Authorities said Nuss told the officer he surrendered to that he had a gun and had brought the children from Pennsylvania to the outskirts of the nation's capital against their will.
"He said he wanted to show them Washington D.C.," FBI spokesman Peter Gulotta Jr. said.
Nuss picked up the students, ages 7 through 15, at a high school in Oley, Pa., at about 7:30 a.m. for a six-mile trip to the Berks Christian School in Birdsboro, Pa. The bus never showed up at the school northwest of Philadelphia.
After a frantic search by residents, a police helicopter and cruisers in rainy, foggy weather, the bus and the youngsters were found 115 miles away, parked outside a Family Dollar store in Landover Hills.
"They made a different turn, and next they know, these children ended up here in Prince George's County," Gulotta said.
Nuss walked into the store and approached off-duty Officer Milton Chabla, telling him he had left a gun on the bus, police said.
Nuss told Chabla he had taken the children against their will and wanted to turn himself in. "He wanted the kids to be OK and let their parents know they were OK," said Chabla, who was wearing his police uniform at the store.
The gun was a loaded semiautomatic rifle. Gulotta said it was found behind the driver's seat, covered by a coat.
Cindy Calcagno, assistant transporttion director for the Oley Valley School District, said Nuss had not driven a school bus before this year. He would have had to pass a commercial driver's test, a criminal background check and a child abuse check to be hired, she said.
"I had no inclination there, and nothing from the children either," she said. "He loved the kids."
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