The regulator has redrafted its guidance on campaigning after being told by the Government to be less prescriptive.
Last year's Private Action, Public Benefit report, which has formed the basis of the Government's reform of charity law, said that the commission's guidance on charities' political activities and campaigning was "too cautionary".
The new guidance, which is out for consultation until the end of July, stresses that charities can take part in demonstrations and direct action, though it warns that such activities also "present real problems of control".
It emphasises that a charity can spend all its resources, if it chooses, carrying out a non-political campaign that furthers its purposes. But where the campaign is political, the trustees must not let these activities dominate the charity's whole purpose.
Caroline Cooke, the commission's head of regulatory policy, said: "While the law relating to charities' campaigning and political activities remains unchanged, we've been able to clarify the freedoms and flexibilities that exist. Our revised guidance focuses on the positives, and we hope that it will encourage and support trustees in reaching their own decisions about what's right for their charity."
Steve Tibbett, director of campaigns and policy at War on Want, a charity which has in the past faced sanctions from the commission for "political" advertising, said he welcomed a relaxation of the guidelines.
"Anything that allows us to be more forthright in our campaigns and not constantly worrying about charity law has got to be a good thing," he said. "At the moment, there is always confusion for trustees. They always have it at the back of their minds, so they go through any activities with a fine tooth comb."
But he added that the commission "hasn't gone far enough" in reassuring charities they could take part in demonstrations and peaceful direct action.
"They seem to have taken two steps forward and one step back," he said.
"Demonstrations are an integral part of campaigns. Many charities use confrontational methods to gain people's attention. In this crowded world of communications and media, you need to do that. I'm not sure the Charity Commission is completely conversant with this."
However, the new guidance does not echo the Community Fund's regulations, which states charities cannot be "doctrinaire". The fund introduced that restriction after the controversy over its grant to the National Coalition of Anti-deportation Campaigns.