WU Senior Class Treasurer Regis Murayi speaks at a news conference, along with Senior Class President Fernando Cutz and the five other students alleging racial discrimation by the Original Mothers bar. (Matt Mitgang | Student Life)

For all of Chicagoland’s storied toughness, Washington University’s Class of 2010 made fast work of a Second City saloon — The Original Mother’s bar — when the Near North Side establishment displayed some seriously bad manners.

About 200 Wash U students on a senior class trip piled into the nightclub on Oct. 17, a Saturday night. Six classmates — Regis Murayi, Iboro Umana, Franklyn Pandolf-John, Nick Brooks, Blake Jones and Chuka Chike-Obi — all African-American, were turned away.

Management claimed the six violated the club’s “no baggy pants” dress code. The larger group of students swung into action. A white classmate put on a pair of the offending trousers. He sailed through security. Now Mother’s had a bigger problem on its hands.

The students immediately drew up a press release and blanketed media outlets. They filed complaints with local government agencies that have authority in cases of alleged illegal discrimination. They solicited and received support from students at Chicago colleges and universities, including Northwestern, Loyola, DePaul and the University of Chicago.

According to Student Life, Washington University’s student newspaper, dozens of students staged a protest the following day. They developed fliers, one for each student denied entry, featuring photos and outlining academic credentials, headlined “Would you have a problem with this guy in your bar? Our Mother’s Bar did.”

There was a time when protesting students had to muscle their way into university administration buildings. This time, Washington University Chancellor Mark S. Wrighton followed the students’ lead — firing off a stiff letter to Chicago Mayor Richard M. Daley.

Mr. Wrighton called what happened “a setback for the city,” that “reveals that we still have much work to do to achieve true racial equality in this country.”

He asked Mr. Daley to investigate and “take the steps necessary to ensure that similar incidents do not occur to future visitors to the City of Chicago.”

Last Wednesday, Mother’s cried “Uncle.” The management company that operates the bar agreed to apologize separately to each of the six students, issue a public apology to Washington University’s senior class and put all of its managers through diversity training. The nightclub agreed to host several fundraisers, with the proceeds going to community groups.

What a remarkable outcome — distinguished by how rapidly and effectively the students came together, built a larger coalition and attacked a very tough problem. There was constant action, but no grandstanding. The six students didn’t lawyer up and seek financial settlements. They pushed for a larger, more powerful resolution.

Now some Washington University students are organizing a follow-up demonstration against racism in Chicago later in November. They expect to be joined by students from Chicago-area universities and employees from Mother’s bar.

While in Chicago, if they are looking to right another injustice, the group might consider swinging by to see Cook County State’s Attorney Anita Alvarez.

Ms. Alvarez is trying to bully some journalism students at Northwestern University. She’s subpoenaed the “grades and grading criteria, evaluations of student performance” as well as e-mails, unpublished memos and “interviews not conducted on the record” from a student team that developed powerful evidence that a man who has spent 31 years in prison may have been wrongly convicted.

Ms. Alvarez is out of line and deserves a visit from the Wash U Six and their many friends.