Thomas Mair (murderer)

The incident was the first killing of a sitting British MP since the death of Conservative MP Ian Gow, who was assassinated by the Provisional Irish Republican Army in 1990, and the first death of a politician in the United Kingdom during an attack since county councillor Andrew Pennington was killed in 2000.

At the next hearing on 23 June, the judge said the case would be handled as part of "the terrorism case management list", on which cases related to terrorism as defined by the Terrorism Act 2000 are placed.

Jo Cox was elected to represent the parliamentary constituency Batley and Spen at the 2015 general election, having spent several years working for the international humanitarian charity Oxfam.

She was married and had two young children.

On 16 June 2016, Jo Cox, a British Labour Party politician and Member of Parliament (MP) for Batley and Spen, died after being shot and stabbed multiple times in Birstall, West Yorkshire.

In November 2016, 53-year-old Thomas Alexander Mair was found guilty of her murder and other offences connected to the killing in an act of terrorism.

The judge concluded that Mair wanted to advance white supremacy and exclusive nationalism most associated with Nazism and its modern forms.

He was sentenced to life imprisonment with a whole life order.

On 16 June 2016, Cox was on her way to meet constituents at a routine surgery in Birstall, West Yorkshire, when Thomas Mair shot her twice in the head and once in the chest with a modified .22 hunting rifle then stabbed her fifteen times outside a library on Market Street.

Cox died of her injuries shortly after being admitted to Leeds General Infirmary.

She was 41 years old.

Retired mines rescuer Bernard Carter-Kenny, 77, was also stabbed when coming to Cox's aid; he was subsequently awarded the George Medal for his bravery.

Another witness followed Mair and identified him to police.

Mair was arrested about a mile from the murder scene by unarmed police officers PC Craig Nicholls and PC Jonathan Wright, who were later awarded the Queen's Gallantry Medal.

The perpetrator of the attack was Thomas Alexander Mair, a 53-year-old unemployed gardener born in Scotland.

Mair had mental health problems, though he was declared sane in the moment of the crime.

He believed individuals of liberal and left-wing political viewpoints, and the mainstream media, were the cause of the world's problems.

Guardian writers suggested that he targeted Cox, a "passionate defender" of the European Union and immigration, because he saw her as "one of 'the collaborators' [and] a traitor" to white people.

Mair had links to British and American far-right political groups including the neo-fascist National Front (NF), the United States-based neo-Nazi organization National Vanguard (the successor to the defunct National Alliance) and the English Defence League (EDL); he had attended far-right gatherings and purchased publications from the National Vanguard and other outlets, to some of which he had sent letters and expressed support for South African apartheid.

In his home were found Nazi regalia, far-right books, and information on the construction of bombs.

He had searched the internet for information about the British National Party (BNP), South African apartheid, the Ku Klux Klan, prominent Jewish people, matricide, white supremacy/nationalism, Nazism/Nazi Party, SS/Waffen SS, Israel, mass shootings, serial killers, Frazier Glenn Miller Jr., William Hague, Ian Gow (another assassinated MP), and Norwegian far-right terrorist Anders Behring Breivik (about whose case he collected newspaper clippings).

He also owned Nazi iconography and books and films related to the Nazis.

A police official described Mair as a "loner in the truest sense of the word... who never held down a job, never had a girlfriend [and] never [had] any friends".

The Guardian said that he "appears to have fantasised about killing a 'collaborator' for more than 17 years, drawing inspiration from" David Copeland.

The evening before killing Cox, Mair visited a treatment centre in Birstall seeking help for depression; he was told to return the next day for an appointment.

Mair's health was not part of the defence case in the trial.

After his arrest, he was examined by a psychiatrist who found no evidence that Mair's mental health was so impaired that he could not be held responsible for his conduct.

On 18 June 2016, asked to confirm his name in Westminster Magistrates' Court, Mair said, "My name is death to traitors, freedom for Britain."

His lawyers said there was no indication of how he would plead.

Mair was remanded in custody and the magistrate suggested he be seen by a psychiatrist.

At a bail hearing on 20 June, the judge remanded Mair in custody until a hearing to be held "under terrorism-related protocols".

At a September 2016 hearing, Mair's counsel said they would not advance a diminished responsibility argument.

At another hearing the following month, Mair—again appearing by video link—refused to enter a plea; the judge entered not-guilty pleas on his behalf.

Mair's trial began at the Old Bailey on 14 November 2016.

He made no attempt to defend himself.

Witnesses testified that during the attack, Mair had cried out "This is for Britain", "keep Britain independent", and "Britain first".

On 23 November 2016, the jury took about 90 minutes to convict Mair of Cox's murder, grievous bodily harm against Bernard Carter-Kenny, possession of a firearm with intent, and possession of a dagger.

In October 2020, a press report stated that West Yorkshire Police's Homicide and Major Enquiries Team (HMET) continued to investigate how he acquired the weapon used, which remains a mystery.

The lack of communication on Mair's phone was described by Detective Chief Inspector Nick Wallen, who led the investigation into Mair, as not indicating someone who was "immersed in criminality".

A West Yorkshire Police spokeswoman said: "A lengthy investigation was carried out to try and establish how Thomas Mair acquired this firearm. All lines of enquiry have for the time being been exhausted, but the investigation will be revisited if further information comes to light."