Transcript for United Airlines faces backlash over leggings controversy

two girs from boarding a night because they were wearing leggings. There's much more to the story and ABC's Diane Macedo is going to have all that for us. Diane if there is, robin. A series of tweets from just one passenger has fueled a full on firestorm. Celebs and others are now blasting the airlines' dress code as sexist and intrusive. This morning, united airlines is dealing with a different kind of turbulence after two girls had to change clothes before boarding a flight from Denver to Minneapolis Sunday. We heard the gate agent say, you know, these aren't my rules. I just enforce them. And that was when they looked very panicked. Reporter: Outraged fellow passenger and activist Shannon Watts took to Twitter writing a united gate agent isn't letting girls in leggings on a flight. Win when does united police women's clothing. To me it seems like a sexist policy respiratory united says it was riding under its pass rider program where employee relatives and friends can fly free or at heavily discounted prices and the airline tells ABC news when taking advantage of this Ben put all employees and pass riders are considered representatives of united. The passengers this morning were united pass riders and not in compliance with our dress code for company benefit travel. With these buddy passes there is specific language about what is appropriate and inappropriate. The airline is saying if you are going to fly for free for us, you are going to meet certain standards of dress. Reporter: But many turned to social media disappointed in how united handled the situation. Some even pointed to the airline's post from last Yuen showing a woman wearing leggings at the airport for international yoga day. Celebs are weighing in too. Chrissy Teigen writes I have flown united before with literally no pants on, just a top as a dress. And Patricia Arquette had a back and forth with the carrier. At one point replying, leggings are business attire for 10-year-olds. Their business is being children. In the end united says the family was still able to travel on the next flight using their passes and reassures its regular customers that leggings are welcome. And many women are now responding with the #stopshaminggirls. One man took a different approach. It's knoll going to be pretty but he plans to wear leggings on his next united flight. Let's just hope they didn't start a new trend. Oh, no. They're not going to start one with David and I. No leggings. We didn't tweet. Definitely was not our tweet. I wonder how long ago the rules were -- that they came up with them. A lot of girls wear leggings. Again, that was for their particular policy. Wasn't for all passengers. It's not just leggings, ripped Jean, midriffs, flip-flops and so on. Diane, thank you.

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