The men and women of peace activist group Code Pink are well known in Washington DC for loudly disrupting congressional committee hearings and heckling politicians mid-speech. And that is just fine with the authorities.
Minutes into US Secretary of State John Kerry's opening statement to the Senate committee about the US campaign of air strikes against Islamic State militants on Wednesday, a woman in pink stood, held up a protest sign and started shouting.
"More invasion will not protect the homeland," the woman cried out five times, forcing Kerry to pause as the committee chairman banged his gavel.
Kerry, who had earlier acknowledged the activists in the audience and referred to his own 1970s-era protests against the Vietnam War, departed from his prepared remarks.
"There's no invasion," he said, as officers with the US Capitol Police force pushed the woman from the room.
Code Pink was founded in 2002 as a grassroots protest group to counter the push by then-President George W Bush for war in Iraq. And among its first actions was singing an anti-war Christmas carol outside then-Defence Secretary Donald Rumsfeld's house in Washington.
Throughout the war in Iraq, the group demonstrated at military recruiting centres, security summits and administration officials' speeches, and became a fixture, however unwelcome, at congressional hearings on defence matters.
When Iraq receded as an issue during the Obama administration, the group demonstrated in support of Wikileaks leaker Bradley Manning and against military action in Iran, among other issues.
But as President Barack Obama has pressed a campaign of drone strikes against militants in Yemen and Pakistan and launched the air campaign against IS, the group's anti-war mission has been revitalised.
"Just as we wanted to show when there was drumbeat for war in Iraq in 2002-3, we want to show that there are Americans who are alive and kicking and thinking and know that this is wrong," says the group's co-founder Medea Benjamin, a petite woman whose vocal energy and willingness to be manhandled by burly policemen belie her 61 years.
"Our voices help give people inspiration to speak out themselves, and to get involved - whether it's signing a petition or calling their congresspeople or coming out to a rally."
The group are well known to the Capitol Police, to members of Congress and their staffs, and to the news media who cover them.
That they are largely greeted in Washington with eye rolls - or at worst, a night in jail - is a testament to America's tolerance for dissenting speech and political assembly, Benjamin and US capitol officials agree.
Benjamin says that the activists launch their actions knowing full well they face arrest - and that knowledge frees her psychologically, for example, to berate the president of the United States for authorising drone strikes in Yemen before an international television audience.
"We don't like getting arrested - it takes time and it's expensive and takes lawyers," she said. "But we've been arrested dozens of times."
Benjamin has also been denied entry into Canada and Egypt, where she says an Egyptian policeman fractured her shoulder attempting to force her onto a plane out of the country.
But in Washington, the Capitol complex and committee hearings are by law and democratic tradition open to the public unless secret intelligence matters are being discussed.
The police who guard the Capitol complex will not ban serial disrupters from the premises unless a judge deems extraordinary circumstances warrant it.
"The US Capitol Police respects and protects the right of people to peaceably assemble and exercise their rights under the First Amendment" to the US constitution, spokeswoman Lt Kimberly Schneider said in a statement. "We balance providing security with maintaining a safe and open campus that is accessible to the general public."
In 2007, for instance, a Code Pink activist was charged with disorderly conduct and assault on a police officer and banned from the Capitol premises after she waved her red paint-covered hands inches from the face of then-Secretary of State Condoleezza Rice and shouted "war criminal".
And last year, a judge controversially banned an anti-abortion activist from entering Washington for a month after he climbed a tree during Mr Obama's 2012 inauguration, shouted anti-abortion slogans and for five hours refused orders to descend.
Political demonstrations are forbidden in the buildings of the Capitol Hill complex. If the Capitol police observe a demonstration they will ask the protester to cease, and if they refuse they face arrest.
The Senate and House committees have their own rules, and some chairmen and women are more lenient of protest than others. People such as Benjamin and her co-activists who demonstrate in a hearing will be removed, by force if necessary but typically with their co-operation.
Their names are run for outstanding warrants, and they are either told not to re-enter the hearing or, depending on the rules of the committee and the specific behaviour, arrested and charged with disruption of Congress or another violation.
But by and large, Benjamin said she and her fellow activists have a sort of working relationship with the officers, who often greet them cordially as they wait in line outside a hearing room in the morning.
"We respect each other, we even like each other," she said. "There can be a bad apple here among them, just as they probably think the same about us.
"They see us in the morning and they start laughing and joking and say, 'Give me a hug now because I might have to arrest you later.'"
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