Our fine tradition of staging peaceful and orderly demonstrations has been called into question once again. On Sunday, a march in support of Chief Executive Leung Chun-ying turned rowdy, with individual participants clashing with some anti-Leung activists. Television footage showed two journalists covering the event in Victoria Park were also mobbed by angry protesters. With both camps are taking to the streets again today, cool heads are needed to avoid further stand-offs and violence.

The rallies and demonstrations today are expected to be even more antagonistic in that the chief executive's opponents and supporters are seeking to drown out each other with a high turnout. The pro-Leung groups, just like the opposition, are equally entitled to demonstrate their support for the city's beleaguered leader. Hong Kong, after all, is a pluralistic and free society. There are people who question the chief executive's integrity in the wake of his illegal structures scandal and want him to step down. At the same time, there are those who are tired of political bickering and are eager to move forward.

Both groups have the same right to express their views under the Basic Law. However, that right must be exercised in a peaceful and orderly manner. No matter how strongly the rivals disagree with each other, they are required to abide by the law. The use of force is unlikely to win them any sympathy. Confrontational tactics should be avoided. Violence must be condemned and punished accordingly.