Shannon Guess Richardson, 35, made an initial court appearance on Friday after being charged with posting a threatening communication to Obama.
She could face up to ten years in prison if convicted.
Richardson, a mother of five who played bit roles in television shows including the Vampire Diaries and the Walking Dead, was arrested for allegedly posting the ricin-laced letters to the White House, New York mayor Michael Bloomberg and a Washington gun-control group last month.
The letters threatened violence to those who advocated gun controls. But Richardson’s court-appointed attorney, Tonda Curry, said there had been no intention to harm anyone. She said it was common knowledge that anything sent in the US post would be screened before it was delivered to any of those allegedly targeted by Richardson.
“From what I can say, based on what evidence I’ve seen, whoever did this crime never intended for ricin to reach the people to which the letters were addressed,” said Curry.
She added that she has met Richardson only briefly and has so far onloy had limited talks with her.
FBI agents wearing protective, hazardous-material suits were seen at Richardson’s house on Wednesday in New Boston, north-east of Dallas, Texas.
Officials said the search began after Richardson contacted the FBI and implicated her husband, Nathaniel Richardson, 33, an army veteran. His solicitor, John Delk, said on Thursday his client was divorcing his wife and suggested that he had been set up.