Early Saturday, he was arrested without incident at home. He was charged with possession and use of a biological agent as a weapon in connection with the letters.
This isn't his only brush with the law.
Dutschke faces molestation charges in an unrelated case.
According to a grand jury indictment handed up this month and obtained by CNN, Dutschke is accused of molesting three girls under the age of 16. He has repeatedly denied the charges in interviews with local media and pleaded not guilty in court this month.
Dutschke closed his tae kwon do studio after the allegations were made public.
Dutschke was previously convicted on indecent exposure charges in another case and sentenced to 90 days in jail.
A song in his heart
As for Curtis, he told CNN he's "just glad it's over."
When he learned Dutschke had been arrested, he took a deep breath and felt like "a weight had been taken off."
"I just want to return to my kids and my music," Curtis said.
During another interview with CNN last week, he said the public attention could "thrust him into the limelight."
And then, at the urging of reporter Chris Cuomo, he burst into song.
A rousing rendition of Randy Travis' "On the Other Hand."