Baha'is cannot participate in demonstrations for peace but they themselves can organize demonstrations if it serves their interests!

Over 180 Baha'is and non-Baha'is march from Baha'i House of Worship (Lotus Temple) to Iskon temple on 1st April 2012 to protest the "illegal detention" of Yaran. The program was in collaboration with U4I and two other organizations, namely, Asian Centre for Human Rights and Trans Asia Alliance.

The Universal House of Justice, Department of the Secretariat states:

…You state that there are large-scale demonstrations…and you inquire about the appropriateness of Bahá'ís participating in demonstrations for peace.…while these activities are generally carried out in the name of peace, such occasions are motivated by highly political and controversial sentiments at a time of turmoil and confusion in the world.… to become associated with such activities, it could also be harmful to the interests of the Faith internationally. … As you can no doubt understand, Bahá'í participation in public demonstrations involving controversial issues would undermine the Faith's essential purpose of promoting unity in all aspects of human affairs…

(2003 Mar 27, Participation in Anti-War Demonstrations)

How Baha'i Politics works? Check some UHJ letters here