Prosecutors warned Penn State student Collin Rowe about defense attorney Karen Muir.

"You called my client a douche?" Muir asked him during a cross-examination at a preliminary hearing. "Do you even know what a douche is?"

She was defending Collin A. Flood, 24, who police say assaulted Rowe on July 31 inside the bathroom of McDonald's, 442 E. College Ave.

Sitting at her desk inside her 1315 S. College Ave. office last week, Muir smiled as she recalled the heated moment.

"That's my reputation. I'm known for being fierce," Muir, 44, said.

Now she's using her ferocity to defend clients in some of the Penn State community's most prominent cases.

She's representing Sammark Inc., the owner of Tony's Big Easy, and two other downtown bars, which is asking the state to let it keep its liquor license.

She also represents Penn State student Murad Hanif, 25 -- the man who left the country the same day authorities charged him with two felony counts of rape -- and Penn State student and boxer Katongo Mulenga, 24, who police say plotted to kill a police informant last semester.

Throughout her career, Muir said she has not cared whether her clients are guilty, despite her suspicions. Instead, she focuses on making sure the law is fairly applied and equally upheld.

"I see good people at their worst moments in life," Muir said. "It doesn't matter to me if they did or did not do the act."

But during Flood's preliminary hearing, Muir's focus was on Rowe and the alleged attack at the McDonald's urinal.

"Right when she asked me if I literally knew what a douche was, I was like, 'This is not going

to go well,' " Rowe (senior-hotel restaurant management) said. "She's all the things people hate about lawyers wrapped into one thing."

Her first battle

Muir said she's just doing her job the best she can, whether that means aggressively questioning those involved with a case or waking up in the middle of the night to write down an idea about a closing argument.

"As soon as I walk into that courtroom: Game on," she said.

But while Muir was growing up, she often had to sit on the sidelines.

Her parents, Leon and Linda Muir, said their daughter had open-heart surgery when she was five years old. Doctors discovered a hole between her two heart chambers, and surgery was required.

While Muir downplayed the surgery -- "I don't see it as a hardship or anything detrimental," she said -- her family says it helped her become a more determined person.

"She was always a fighter," Linda said.

"She was lying there on a table with all of these tubes," Leon said. "She was so young whenever it happened. She was scared being down there."

But her medical struggle is only one example of Muir overcoming adversity. When her father took the training wheels off his daughter's bicycle, she kept falling off and getting scrapes on her arms and knees. People in Philipsburg -- her hometown -- started talking, he said.

"They wanted to know if I was beating her," Leon said, laughing.

No one expected the daughter of a nurse and a school principal to become an attorney, her parents said.

Muir said she couldn't pinpoint an exact moment when she knew she wanted to become an attorney, but she mentioned a particular family vacation and a high school internship.

When she was about 12 years old and went sailing on a family vacation at a lake in Clarion, Pa., police issued her a citation because her life jacket didn't have the proper codes on it, she said. It was one of her first brushes with the law.

A few years later, she made time to intern at a local law firm when she wasn't playing the clarinet or saxophone in her high school marching band or starring as the title role in her high school's musical production of Hello, Dolly!

"She has an artistic flair, but she's not the best actress in the world," Linda said. "She wanted the role, she worked hard for it and she achieved it."

Muir attributes her personality traits to her mother and her work ethic to her father.

After high school, she went on to obtain her law degree at Ohio Northern University after graduating from the Indiana University of Pennsylvania in three years.

"She does some phenomenal things," her father said. "She's a very determined girl."

Realizing her dreams

Her parents saw that same determination when they watched her defend former Penn State football player LaVon Chisley in September 2007 at the Centre County Courthouse.

"There she was -- at one table with all these boxes and notes," Linda said.

Chisley, then 23, was ultimately found guilty of killing Penn State student Langston Carraway.

"It's still a case that haunts me," the attorney said. "I was devastated. I didn't expect to have that strong of an emotional response."

Chisley was found guilty of first- and third- degree murder after police said he stabbed Carraway 93 times in the neck, chest and abdomen, according to court documents.

Muir tearfully hugged Chisley's father after the guilty verdict was announced.

Leon said his daughter put a lot of "hard work" into the Chisley case, an attribute she first exhibited as a toddler.

She'll need it -- she has a lot on her plate with this fall's cases, but Muir said there's nothing else she would rather do than to be an attorney. Her experiences have given her a unique sense of humor and "the ability to compartmentalize," she said.

Her parents said they are extremely proud of their daughter. The sky is the limit for Muir, her mother said.

"Karen has worked very, very hard in her life and is realizing some of her dreams," Linda said. "She has additional aspirations to attain -- she's not one to build something and stagnate there."