The sentencing hearing for 36-year-old Shannon Guess Richardson is set for Wednesday in federal court in Texarkana, Texas.
Richardson pleaded guilty in December to possessing and producing a biological toxin. Her attorney says that under the plea deal her prison time would be capped at 18 years.
Richardson was arrested in June 2013 after authorities said she tried to implicate her estranged husband after he filed for divorce. Prosecutors say Richardson, who had minor acting roles in film and television, mailed three letters from New Boston, outside Texarkana, then went to police and claimed that her husband did it.