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PHILADELPHIA — Wearing his Vikings-themed leisure suit, Justin Rustad expected jeers as he walked through the Eagles crowd before the NFC championship game last week.

As a Vikings season ticket holder and a frequent visitor to other stadiums, Rustad, of Two Harbors, Minn., knows the drill: Opposing team fans heckle him when he visits their stadiums, and he dishes it out while tailgating at home. He does it with a smile, he said, and often ends it by offering a beer and good luck.

But after Rustad got shoved and cursed in Philadelphia, he pronounced the environment hateful: "We had people tell us, 'This is how we are.' " he said. "Well, why? You can change your behavior."

Maybe, sports psychologists and sociologists say. But it won't happen easily or quickly.

With some of the NFL's most obnoxious fans meeting up in Minneapolis for Sunday's Super Bowl clash between Philadelphia and New England, experts say that fan group behavior — good and bad — can be difficult to change. Deep loyalties to sports teams form early in life and are often passed down through generations, establishing a culture of conduct surrounding teams that is encouraged and celebrated.

"Different fan groups have different sets of norms of how they behave … what they do and don't do, their traditions, their cheers," said Nicole LaVoi, a social psychologist of sports at the University of Minnesota. "The only way norms really get changed is if a majority of people in that culture buy the norm. If all of a sudden the NFL said, 'We want our fans to be the best fans, the most respectful fans' … it's basically lip service unless the fans themselves say 'This is how we do it.' "

Change is hard

A certain amount of taunting and poor behavior happens at all major sports events, sports psychologists say. But how does a fan culture degenerate into something that gets a bad reputation?

Research shows people "will do things in the context of sport that they would never do outside of the context of sport," LaVoi said. "People feel like they get permission, that it's OK to act in these ways during a game."

The anonymity that comes with being one of many at a stadium helps fans feel uninhibited, said Rick Grieve, a professor of psychology at Western Kentucky University, who researches sports fans.

It's the intensity and frequency of the behavior that earns reputations among teams, analysts say.

A subset of what some psychologists call "dysfunctional fans" — those who enjoy confronting others at games — can have a big impact, even though they are in the minority.

"If you've got a crowd of 60,000 people and 500 of them want a bad reputation, that's about all it takes," said Dan Wann, a psychology professor at Murray State University in Kentucky.

Vikings fans and media observers recounted many incidents of poor treatment in Philadelphia. In addition to fans being pelting with cans of beer and vulgarities, one Eagles fan stuck phallic symbols in people's faces, others made sexual gestures.

After a young boy screamed in the face of a middle-aged woman in purple, a man who appeared to be his father apparently approved, smiling and saying, "Gotta raise 'em right."

Later, inside McGlinchey's Bar in downtown Philadelphia, city residents gave varying explanations for the Eagles fan reputation.

"New York and D.C., they get more of the spotlight," said Al Davis, who works at the bar. "Nobody gives us respect … You fight for it … the whole Rocky attitude."

Patron Jimmy Stephens said he's never been an Eagles fan — or a fan of the fans.

"You see … drunken meatheads here booing Millie. What's wrong with you all?" Stephens asked about Eagles fans shouting curses about 99-year-old Vikings fan Millie Wall. "The city wonders why they're always the underdog. Why wouldn't they be if they treat people like [expletive]?"

Interventions

Even if most fans want their culture to change, it would take a concerted effort and time, sports psychologists said.

For the majority of fans who disparage poor behavior, fandom may make it difficult to intervene, Grieve explained.

Sports can bring a lot of positives to people's lives. Studies have shown that the more people are connected to a local team, the better psycho-social health they have, Grieve explained. They are less lonely and more trusting of people around them.

Fans of any sport typically think favorably of their fellow fans, assuming they are decent, smart people who have good taste in teams, Grieve said.

"If I see that person acting poorly, I'm going to give them a pass because we're on the same side," Grieve said.

But that's not an excuse, he added: "The people who aren't doing it, but aren't stopping it, are also culpable."

Wann said bystanders are sometimes afraid to confront aggressors, particularly if there's the potential for violence and police won't be able to tell who is intervening.

Some sports teams are sponsoring seminars on bystander intervention for all sorts of situations in society.

Karen Lundgren, of Edina, said one Eagles fan made a big difference at the NFC championship game when others taunted her and her son.

The woman put her hand in the face of a taunter in one case and said "turn around," Lundgren recalled. And he did. "Just one lady, that's all it took to change an experience," Lundgren said.

Change of tune

Psychologists said changing a culture is possible, but it takes a lot of time and work.

It would require promoting a new image at all levels, from the city to the team owners, coaches and players. Then fans have to be willing to embrace it, Grieve and others said.

Both Philadelphia Mayor Jim Kenney and the city's Convention & Visitors Bureau put out statements last week, with the mayor calling the actions of the "knucklehead" fans "disgusting and regrettable."

"We're certain they represent a small portion of the team's loyal and passionate fan base, but the simple fact is that no visiting fan should have to put up with such treatment," Kenney said.

The visitors bureau said leaders were disappointed by the inappropriate behavior of some fans. "Sadly, these kinds of incidents are seen all too often in cities and stadiums around the country." The bureau praised fans who donated money to Vikings Coach Mike Zimmer's foundation, many of whom sent apologies with their donations.

Super Bowl showdown

Time will tell whether Minnesotans will see bad behavior on the streets of Twin Cities this Super Bowl weekend.

"Dysfunctional fans are actually most likely to go to away games because they like that confrontation," Grieve said. "Many times, they will go and try to recreate their home environment in the visiting arena."

That will be a lot more difficult in an event like the Super Bowl, where the stadium isn't packed with fans from the teams' hometowns, he said.

But there can always be isolated incidents, psychologists acknowledged.

"I guess time will tell," LaVoi said. "Right now we just have assumptions."