PORTLAND, Ore. (AP) - An assistant federal public defender found strangled in her Oregon home was strong and athletic and would not have been easily overpowered, family members say.

Nancy Bergeson, 57, of Portland, was found dead Tuesday. An autopsy a day later showed she was strangled. Authorities say they don't have a suspect.

Her sister, Julie McCormick, and others have described Bergeson as a marathon runner, mountain climber, skier and boat paddler. She was strong enough to beat her teenage nephews at arm wrestling so family members don't imagine someone overpowering her.

Bergeson also didn't express concern that a client would do her harm, family members said.

McCormick said her husband is a county public defender and often discussed case strategies with Bergeson.

She didn't talk about fears of retribution or retaliation by clients, McCormick said. "You always worry about that, but this was not a concern she ever expressed," her sister said.

"The irony in this to me is she defended people who committed crimes, and she was such their advocate," McCormick said. "If this person could do something so horrific to her ... She would have been probably their best ally, and this person takes her out. That's what kills me."

A girl who stopped by daily to walk Bergeson's golden retriever saw her face down in the dining room of the southwest Portland home, police said.

At first, officers thought she died a natural death. Because her daughter was healthy, that was puzzling, said Marian Bergeson, her mother and a former California legislator and state education secretary.

When Marian Bergeson called Oregon's medical examiner for an update the next day, she learned that the autopsy showed the death was a homicide.

"That was, of course, like a double whammy," she said. "You just couldn't conceive of that sort of thing happening to Nancy."

There was no sign of forced entry, and the house wasn't ransacked, police said. The front door was unlocked, but investigators were told that wasn't unusual.

McCormick said the family "needed to be together" for Thanksgiving.

"We sat and we ate," McCormick told The Oregonian newspaper. "You just have to try to figure out how to breathe. It's still such a wicked, numb state. Words don't describe the gaping loss."

Bergeson was divorced. Family members said she had planned to fly to Boston on Wednesday to visit her 23-year-old daughter.

Bergeson kept in touch with her family and had e-mailed her mother last week, relieved that her defense of a man in a tax evasion conspiracy case had wrapped up Friday after three weeks of trial.

Killing a federal government employee because of official duties is a federal crime, so an FBI agent is keeping tabs on developments.

"We are watching the case and staying briefed on thecase in the event that down the road, the homicide was related to her employment," said FBI spokeswoman Beth Anne Steele.

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Information from: The Oregonian, http://www.oregonlive.com

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