A national right-to-die group that was convicted of helping an Apple Valley woman end her life is now asking a federal judge to declare that Minnesota's prosecution violated the group's free-speech rights.

The Final Exit Network, a Tallahassee, Fla.-based nonprofit, sued Minnesota Attorney General Lori Swanson late Monday after exhausting its efforts to appeal its convictions of assisting a suicide and interfering with a death scene delivered by a Dakota County jury in 2015.

Attorneys for Final Exit argue that a critical element of a statute used to prosecute the group — assisting a suicide — amounts to "pure First Amendment-protected speech."

Benjamin Wogsland, a spokesman for Swanson, said the Attorney General's Office is not an appropriate party in the case and that they plan to ask that it be dismissed.

Dakota County prosecutors charged Final Exit in 2012 in connection with the suicide of Doreen Dunn, a 57-year-old Apple Valley woman who took her life shortly after contacting the group in 2007. Dunn told Final Exit counselors that she had suffered from unbearable pain for a decade, but did not disclose to family her plans to commit suicide.

In the group's federal civil complaint, Final Exit says it provides "information, education, counseling, and emotional support to persons who are competent, suffering intolerably, and who make an informed choice to hasten their deaths."

The group has vowed to continue operating in Minnesota despite the conviction, which led to a $33,000 fine and nearly $3,000 in restitution. Robert Rivas, an attorney for Final Exit, has maintained that prosecutors presented no evidence of assistance, only of advising and encouraging a suicide, which are protected as free speech in Minnesota.

Since the Dakota County prosecution, Final Exit said it had become much more aggressive about seeking out loved ones and relatives, and people with mental illness are more carefully evaluated.

In 2016, the Minnesota Court of Appeals affirmed the ruling, which was the group's first felony conviction.

The Appeals Court ruled that state law doesn't prohibit the group's policy advocacy for the right to die or the emotional support it provides members by listening to their stories. It also ruled that the corporation wasn't convicted on the issue of free speech but for instructing someone on suicide methods.

Two years before trial, both the Appeals Court and Minnesota Supreme Court ruled that the "advises" and "encourages" clauses of the statute were unconstitutional. The Supreme Court in an unrelated case that was also pending at the time, struck the clauses from the statute but interpreted the word "assists" to criminalize speech that "enables" a suicide.

Both the Minnesota Supreme Court and U.S. Supreme Court declined to review Final Exit's appeals. Final Exit's attorneys said the Dakota County jury convicted the group "based on its open practice of providing instructions to its members" like Dunn and said that Final Exit's instructions are freely available online, in bookstores and at libraries around the country.

At trial, prosecutors argued that the group gave her a "blueprint" for ending her life by asphyxiation and made efforts to conceal her suicide from family and authorities by removing evidence.

Rivas and Paul Engh, Final Exit's attorneys, are now also asking that Minnesota be barred from any additional prosecutions of the group and its personnel based on "the utterance of 'speech' that 'enables' a 'suicide.' " The group's attorneys argue that it is "in constant danger" of being prosecuted again.

Stephen Montemayor • 612-673-1755 Twitter: @smontemayor