A woman who faces criminal charges stemming from a party at which a 14-year-old girl died after inhaling helium was arrested today on suspicion that she tried to get a witness to lie in her upcoming trial.

A woman who faces criminal charges stemming from a party at which a 14-year-old girl died after inhaling helium was arrested today on suspicion that she tried to get a witness to lie in her upcoming trial.

Detectives arrested Katherine McAloon, 28, on a charge of tampering with a witness, Medford police said. She was lodged in the Jackson County Jail on $4,000 bail, but is no longer listed as an inmate, jail records show.

Police said an investigation revealed McAloon was attempting to have a witness lie in her upcoming trial on a charge of first-degree criminal mistreatment, seven counts of delivery of marijuana to a minor and seven counts of furnishing alcohol to a person younger than 21. The trial is set for February 2013.

McAloon hosted a party last February at her apartment in Medford, where a group of teens allegedly drank alcohol, smoked pot and inhaled helium from a compressed gas canister. She is the older sister of one of the teens.

At the party, 14-year-old Ashley Long, of Eagle Point, collapsed and died when she suffered an embolism after breathing in helium.