The Nebraska Supreme Court has been asked to decide if alcoholism can be considered a mental illness in determining whether to commit sex offenders.

7 State Supreme Court Justices heard argumnets Wednesday.

The case involves a man found in 2008 by the state's mental health board in Omaha to be a dangerous sex offender in need of inpatient treatment. The board's decision to commit the man was based largely on a psychiatrist's finding that the offender suffered from alcohol dependence.

The man, who had sexually assaulted his 42-year-old sister and 9-year-old niece, is referred to only as "G.H." in appeal documents.

One of the man's public defenders, Zoe Wade, said civil commitment hearings are closed proceedings and that state law prevents her from disclosing details of the man's case.

The attorney for the state in the case, Deputy Douglas County Attorney Jeff Lux, did not return multiple messages left by The Associated Press seeking the man's name or details about his criminal past.

The man's lawyers argue, among other things, that the Douglas County District Court erred in considering a diagnosis of alcohol dependence as a mental illness. The court noted that alcohol dependence is not among the definitions of mental illness in the Nebraska's Sex Offender Commitment Act.

Defense attorneys also argue that the evidence in the case does not support a finding that the man suffered from alcohol dependence at the time of the civil commitment hearing.

"Even if substance dependence could meet the statutory criteria for mental illness, the state failed to prove that G.H.'s alcohol dependence impairs his thought processes or ability to reason," the defense attorneys' brief reads.

Lux argues in his brief that even though alcoholism is not included in the definition of mental illness used by the state's sex offender commitment law, a person who is substance dependent can be deemed mentally ill under state commitment laws.

The state sex offender commitment law, Lux writes, says a dangerous sex offender "means a person who suffers from a mental illness which
makes the person likely to engage in repeat acts of sexual violence."

Lux argues that a psychiatrist testified the man's alcoholism would make him likely to re-offend. The man is current being held in an undisclosed facility in the state to undergo sex offender treatment.

Last year, the Nebraska Supreme Court upheld as constitutional a 2006 state law that allows sex offenders to be committed to treatment after serving their prison sentences.