Now, many critics of Blair are asking a couple of simple questions: Do his alleged misdeeds ahead of the 2003 invasion rise to the level of illegality? Could the once-lauded leader of Britain find himself on trial? The Iraq War certainly seems to have tarnished Blair's reputation in the court of public opinion, but the legal implications are far less clear.
So what legal effect does the Chilcot inquiry have?
Ultimately, none. It is a public inquiry into Britain's role in the Iraq War. It is not a court, and the participants in the inquiry are not lawyers or judges — John Chilcot, the man leading the investigation, is a former civil servant. They cannot make legal judgments and have not sought to.
As such, Chilcot told the news media at the release of the report that it "has not expressed a view on whether military action was legal." He added, however, that the legal justification for British military action in Iraq was found to be "far from satisfactory."
Where are the calls for Blair to face trial coming from?
Calls for the former prime minister to face trial for a war that many felt was illegal have dogged Blair for years. High-profile people, such as South Africa's Archbishop Desmond Tutu, have suggested that he should be tried for war crimes. This year, a petition on Britain's parliamentary website to "arrest" Blair for his role in the war garnered more than 20,000 signatures before being closed.
A notable new addition in the campaign against Blair is from his own Labour Party. Jeremy Corbyn, the leftist politician who unexpectedly won the leadership of the party last year, was a vocal opponent of the war. In August, he suggested that Blair should face trial for the "illegal" war. After the release of the Chilcot inquiry on Wednesday, Corbyn apologized to the Iraqi people on behalf of the Labour Party and said those "laid bare" by the report should face the consequences, although he did not refer to Blair by name.
While damning stuff, Corbyn also is struggling to control his party at the moment and could be ousted from the leadership soon. His chances of leading Britain in the near future are not so impressive.
Could Blair face charges in the International Criminal Court?
In theory, one place where world leaders — both current and former — who have committed war crimes could face trial would be the International Criminal Court, established by the Rome Statute in 2002 to investigate and prosecute when states are "unable" or "unwilling" to do so themselves. Unfortunately, the ICC has a mixed record of going after heads of state. It has tended to pursue only African leaders (in part because of independent war-crimes tribunals in other conflict zones) and struggled to get convictions.
Mark Kersten, a researcher at the Munk School of Global Affairs at the University of Toronto who runs the Justice in Conflict blog, said it is "very unlikely" that Blair will face charges. "The ICC cannot investigate or prosecute the crime of aggression, so the invasion of Iraq is out of its remit," Kersten said. Thus, one of the most popular complaints about Blair's decision to go to war in 2003 — that the war was an "illegal" act of military aggression — cannot be judged at the ICC. As things stand now, that act can really be sanctioned only by the United Nations Security Council, of which both Britain and the United States are permanent members.
Other complaints about conduct during the war are not out of bounds, however. Kersten said that the ICC has started a preliminary examination into allegations of war crimes committed by British citizens in Iraq. ICC prosecutor Fatou Bensouda has said that her team will review the Chilcot report and refuted claims in the British news media that the ICC had already ruled out prosecuting Blair.
It's important to note that the ICC is supposed to step in only if Britain proves unable to investigate itself. Britain has investigated some of these alleged war crimes — army Cpl. Donald Payne received a one-year prison sentence for his role in the death of Baha Mousa, an Iraqi hotel receptionist — and it set up the Iraq Historic Allegations Team to investigate allegations of war crimes committed by British citizens in that country. Yet many activists said that not nearly enough has been done, which would mean that the ICC could be called upon to intervene.
"UK authorities have also shown little interest in investigating whether senior military and political figures are criminally liable for any war crimes," Clive Baldwin, senior legal adviser to Human Rights Watch, wrote Wednesday. "The UK clearly has the law and the resources to bring about these prosecutions. But if it is not willing to do so, the ICC could step in."
Will Parliament declare Blair's decision illegal?
Another intriguing development comes courtesy of Alex Salmond, a politician for the Scottish National Party, who responded to the release of the Chilcot inquiry with a statement calling for "a consideration of what political or legal consequences are appropriate for those responsible."
The Guardian reports that Salmond and a number of his allies are hoping to use an obscure "impeachment" law to have Blair placed on trial. If the law were to be approved, it could see Blair face trial in Parliament. If found guilty, he would be banned from holding office or even, in theory, given a prison sentence, although any punishment would probably be largely symbolic.
Whether Parliament would actually go through with this is unclear: The law is archaic and hasn't been used since 1806. Additionally, many members of Parliament might balk at the idea of punishing Blair for a decision that Parliament had approved. But if Salmond and his allies were to push forward with their plan, it would at least result in more public humiliation for Blair.
Could the families of those killed in the war pursue a legal case against Blair?
The families of British soldiers killed in the Iraq War have been reported to be investigating whether they could pursue their own legal action against Blair. While they may hope for criminal proceedings, a more likely option may be to pursue civil litigation. Gen. Michael Rose, a former military leader representing the families, has previously said that they would move to sue Blair if it was revealed that intelligence was "negligently handled." The families are said to be enlisting a law firm that used a civil case to bankrupt Irish nationalists allegedly linked to a 1998 bombing in Omagh, Northern Ireland.
Civil suits have previously been brought by families of Iraqis allegedly abused by British troops, although they have targeted the Defense Ministry rather than an individual.
What does this mean for other world leaders?
Legal action against Blair would be a game-changer, Kersten said. "Every legal action against a senior political figure, irrespective of where they are from or who they are, would set a precedent," he said, adding that it could be a chance for the ICC to redeem itself in the eyes of much of the world. "I have no doubt that an investigation into senior Western perpetrators of torture, detainee abuse and other war crimes would signal to the world that global justice has no favors and can be even-handed."
But even if no legal action is taken against Blair, the outrage against him may prompt change within Britain and elsewhere. Writing in the Guardian, human rights lawyer Geoffrey Robertson said the idea of putting Blair in the dock is a "fantasy" because of the way international law works. He called upon British politicians to ratify the ICC's aggression amendment and push for British law on the subject.
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