U.S. Magistrate Judge Bernard Skomal also ordered Sharlotte Hydorn to not participate in any way in assisting suicides, including the manufacture of devices or as an adviser to others on the subject.

The conviction was part of a plea deal reached between federal prosecutors and Hydorn after investigators raided her home last year in El Cajon, east of San Diego. She pleaded guilty to failure to file taxes, but under an agreement with prosecutors she will not be charged in state court with involvement in six suicides.

Assistant U.S. Attorney Peter J. Mazza said the government opted to prosecute the retired school teacher for tax evasion because they felt it was the best way to stop her. There is no federal law regarding assisted suicides.

Prosecutors say she sold at least 1,300 kits across the United States and abroad. Most of the recipients contacted her by mail or phone.

Mazza said the federal government never intended to use the case to take a position on assisted suicides, but instead wanted to address the "public risk" of Hydorn's "indiscriminate and un-thoughtful sale of suicide kits."

He said she had no idea whether her kits were being bought by people suffering from depression or by minors acting without the consent of an adult. One of those who committed suicide with her kit was a 19-year-old boy, Mazza said.

Investigators determined that the kits were sold to at least 50 people in San Diego County since 2007 and that four of those people last year used the kits to commit suicide. None was terminally ill, according to investigators.

Hydorn admitted in her plea deal that she manufactured the kits in her home and sold them for between $40 and $60, but has said she did so because she wanted to give the terminally ill the option to decide how they wanted to die.

"To Ms. Hydorn, her involvement in the suicide kits was an act of compassion and not based on greed," her attorney Charles Goldberg wrote in court documents.

Hydorn has pleaded guilty to the tax charge dating back to 2007 and acknowledged that she made more than $150,000 in income from various sources during that period, including from the sale of helium kits.

The judge ordered her to work with the Internal Revenue Service on the amount she owes and pay accordingly. She was also ordered to pay a $1,000 fine.

More on CBS News
May 7, 2012 -92-year-old retired school teacher faces sentencing for selling helium suicide kits