Anyone who has attended a Major League Baseball game in the past decade has probably seen a "Kiss Cam" where couples throughout the ballpark are featured locking lips on the big-screen JumboTrons.

But controversy over ballpark kissing erupted at Safeco Field in Seattle this week when a same-sex couple claimed they were discriminated against because of their sexual orientation, which stadium officials deny.

Sirbrina Guerrero, 23, says she and her partner, who requested anonymity, were just "exchanging pecks," not acting any differently than heterosexual couples at the game, when park officials told them to stop "making out" or leave the facility.

"We were acting the same as any other dates that were out there, except we were a lesbian couple," she said. "When you bring a date to a game, you kiss once in a while. But it's not like we were making out. We were just kissing as regular couples do. I would never make out with anyone at a baseball game."

Stadium officials are investigating the incident, but Safeco Field's code of conduct includes a provision stating that "staff will proactively intervene to support an environment where guests can enjoy the Safeco Field experience free from unacceptable behavior, including … displays of affection not appropriate in a family setting."

Guerrero claims that Safeco failed initially to clarify what affection was "not appropriate," but eventually told her that policy prohibits any public displays of affection, which, in this case, was not shown on the big screen.

"They have a policy that says you can't be conducting in that behavior, but honestly, the Mariners stadium has a kissing camera," Guerrero said. "So I don't understand how they would say you're not allowed to show public affection when they're blasting it across the stadium."

In a crowd of 30,000 people, Guerrero wonders how only one couple were reprimanded for displaying affection.

When asked whether she believes Safeco officials singled her and her partner out solely because they were a same-sex couple, Guerrero said, "Absolutely. Otherwise I wouldn't be so upset about it."

Since the Monday night incident, Guerrero and her partner have filed a formal discrimination complaint against Safeco Field.

"Washington state law says that you cannot be discriminated against, even as same-sex couples at a public event," she said. "And we were. Everyone I've talked to is really upset, because they know it was wrong and they don't agree with the way it was handled."

Washington passed a law in 2006 that specifically bans discrimination of same-sex couples in any public setting.

Rebecca Hale, the Seattle Mariners' director of public information, denies that the couple were singled out because of their gender or sexual orientation.

"We're trying to figure out the actual behavior that happened; it has nothing to do with the individual," Hale said. "We're taking the claim very seriously, but we're trying to talk to everybody and ascertain exactly what happened, and then we will be able to make a decision on how to proceed."

Stadium personnel intervened because of a specific complaint from a mother and her son, Hale said.

"They were responding to a complaint from a fan who thought there was an inappropriate display of affection; there was no subjective singling out by the stadium," Hale said. "We take both parties' concerns seriously, but we can't really say anything because we are still investigating exactly what happened. But I do know that we have a policy in place that is meant to be welcoming to all fans, so all fans can enjoy their experience, regardless of race, sexual orientation, physical ability, etc."

The discrimination claim by Guerrero is not the first time Safeco Field has been at the center of same-sex controversy. In 2004, the stadium was the site of a "MAYDAY for Marriage" rally, in which more than 20,000 people turned out to protest same-sex unions.

Julie Oleson, 25, who, along with several other lesbians, was attending the game with Guerrero, said the rally surfaced in her mind immediately.

"It definitely popped into my head, but I'm from Seattle, and there's an anti-discrimination law. It was still very surprising," Oleson said. "The fact that we were approached and singled out at a baseball game …… it was all frustrating. We were enjoying our $10 tickets like everybody else in the nosebleeds."

Oleson, who spoke to the guest services supervisor when the situation between Guerrero and stadium officials continued to escalate, has been equally frustrated with Safeco's handling of the incident since it occurred.

"After the situation escalated and I had had enough, I went to the security captain," Oleson said. "He actually instead was like, 'Is this just kissing? Oh, this is no big deal, just go back to your seats and enjoy the game.' So first it was a problem, then it wasn't problem. It seemed like the supervisor just tried to sweep it under the rug like nothing happened, I guess hoping we would just let it go."

Guerrero and Oleson have spoken to Safeco officials once since the game.

"I talked with a rep from the Mariners who was looking for more clarification," Oleson said. "She gave an apology, but it was hard to figure out who she was apologizing for, like what was behind it, since she didn't say they did anything wrong. I still haven't gotten a definition of what 'inappropriate behavior' is, but I would like to go to a place where it didn't matter."

Melissa Benites, 25, a friend who attended the game with Guerrero, said the couple filed a formal complaint because it was a chance to make a statement for a greater cause.

"It could have been a situation where we just let it go like it wasn't a big deal, but we felt we needed to stand up for ourselves and more importantly, other same-sex couples."

Guerrero, who has appeared on the popular MTV reality show "A Shot at Love 2 With Tila Tequila," agreed. "This is definitely a greater cause," she said. "I'm a firm believer in equal rights, and I want everyone to know what happened to me so it doesn't happen to them in the future."

The results of Safeco's investigation are still to come but the specific behavior will be the deciding factor, said Mariners spokeswoman Hale, questioning whether the couple were only "pecking."

"I've talked to one girl who we asked to characterize the level of behavior, and she admitted it was affectionate kissing," Hale said. "Now I don't know what that means, but it says to me it was something more than just an innocent kiss. All I can say is that we're still investigating and talking to all parties involved."

The women are still considering their legal options, but have said they will be wary of returning to Safeco Field.

"I've been out for six years and nothing like this has ever happened," Guerrero said. "But it's not the Mariners, it's Safeco. I haven't even received an apology from them or any kind of contact at all."