Third-degree murder carries a maximum penalty of 20 to 40 years in prison.
Austin was scheduled to stand trial April 14 on a first-degree murder charge. If convicted, she could have been sentenced to life in prison.
But prosecutors agreed to a third-degree murder plea to avoid the risks of putting the case before a jury, Latzer said.
For two years, Austin lived with the victim, Samuel Monroe, in a two-story brick colonial on Stanbridge Street. Ownership of the house was in both their names, but after Monroe disappeared, Austin filed documents with the county recorder of deeds to make her the sole owner, court records state.
Latzer called Austin a "con artist," and said Monroe's family feared Austin could have convinced a jury that Monroe had beaten her and that she feared for her life.
"Their concern, as was ours, was that she would con a jury," Latzer said.
Members of Monroe's family declined to comment after the hearing, as did her lawyer, Arthur Jenkins of Norristown.
Monroe, 47, and Austin had a son, born in October 2000, court records state. Monroe was a psychiatric technician who counseled suicidal and drug-addicted patients, his coworkers said.
Austin, a graduate of Boston University, was arrested July 2, 2002, after two Norristown detectives went to her home to investigate a report she had filed two months earlier that her boyfriend was missing.
The detectives were struck by the "overpowering odor" of a decomposing body. They also noticed a lot of flies, and mothballs scattered about the basement, an affidavit states.
With Austin's permission, detectives opened the door to a cedar closet and found Monroe's body.
"What's this?" Detective David Mazza asked.
"It's him," Austin said. "I got sick of his [behavior]."
Austin admitted to police that she shot Monroe after an argument.
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