LONDON — A man with a history of extremist right-wing beliefs was convicted on Wednesday of murdering Jo Cox, a popular Labour Party lawmaker, one week before Britain’s referendum in June on leaving the European Union.
A jury convicted the man, Thomas Mair, 53, of terrorist murder after a seven-day trial at the Central Criminal Court of England and Wales, commonly known as the Old Bailey. He was immediately sentenced to life in prison without the possibility of a parole. He had declined to testify at the trial.
“Mair has offered no explanation for his actions, but the prosecution was able to demonstrate that, motivated by hate, his premeditated crimes were nothing less than acts of terrorism designed to advance his twisted ideology,” Sue Hemming, the head of the special crime and counterterrorism unit at the Crown Prosecution Service, said in a statement.
Prosecutors told the jury that Mr. Mair had stabbed Ms. Cox, 41, 15 times and shot her with a sawed-off .22-caliber hunting rifle on June 16 on a street in Birstall, a town in northern England. The killing stunned Britain, where gun ownership is tightly regulated. It was the first assassination of a sitting member of Parliament since 1990, when members of the Irish Republican Army killed a Conservative lawmaker, Ian Gow.
Ms. Hemming, of the Crown Prosecution Service, described Ms. Cox as “a defenseless mother of two young children who served her constituents with passion, exuberance and vitality and was proud to represent a diverse community.” She noted that several people had tried to come to Ms. Cox’s aid, including a 77-year-old man, Bernard Kenny, whom she said Mr. Mair stabbed and seriously injured.
In addition to terrorist murder, Mr. Mair was convicted of grievous bodily harm of Mr. Kenny, a retired coal miner, as well as possession of a firearm with intent to use it, and possession of a dagger.
“Our thoughts are with Jo Cox’s family, who attended the court hearing and have behaved with real strength and dignity throughout,” Ms. Hemming said in her statement, adding that the prosecutors’ office “will continue to work with criminal justice partners to combat those who seek to sow hatred and division by advancing extremist ideologies.”
Like most members of Parliament, Ms. Cox, who was elected in May 2015 to represent Batley and Spen, a district with a large number of retirees and many residents of South Asian origin, argued against leaving the European Union. But on June 23, nearly 52 percent of voters decided that Britain should leave the 28-nation bloc. Prime Minister David Cameron resigned, leaving his successor, Theresa May, with the weighty task of negotiating Britain’s departure from the union, a process that is just beginning to unfold, creating uncertainty in one of the world’s largest economies and beyond.
The jury was not asked to consider Mr. Mair’s motivations. He had declined to respond to the charges, but his lawyers entered pleas of not guilty on his behalf.
That said, Mr. Mair, an unemployed gardener, had a longstanding obsession with Nazi propaganda, white supremacist ideologies and the apartheid era in South Africa, according to evidence presented in court. The Southern Poverty Law Center, in Alabama, reported soon after the killing that Mr. Mair was a “dedicated supporter” of the National Alliance, a neo-Nazi organization in the United States.