Jeremy Corbyn has defended appointing a peer to his frontbench who went to prison for arson, saying he should play a "full part in public life" after being rehabilitated.
Mike Watson, who pleaded guilty to a charge of wilful fire-raising when he appeared at Edinburgh Sheriff Court in September 2005, was given a job in the shadow education team.
The move was branded as "bizarre" by the SNP, which claimed it was proof Mr Corbyn was "scrambling around" to find people to fill the frontbench roles.
Mike Watson outside court in 2005
Lord Watson admitted setting fire to a curtain when he attended the glitzy Scottish Politician of the Year awards at Edinburgh's 17th-century Prestonfield House Hotel.
The flames destroyed a curtain and burned the curtain pole as smoke spread up over the walls and ceiling before staff managed to extinguish the blaze without fire crews being called.
An SNP spokesman said: "This is a bizarre appointment; it reflects how Jeremy Corbyn seems to be scrambling around for people to work with, which in turn is further proof of the deep divisions within the Labour Party."
But Labour defended the move, insisting the peer had now been rehabilitated.
A Labour Party spokesman said: "Lord Watson was readmitted to the Labour Party in 2012 and following his rehabilitation it is right he should be allowed to play a full part in public life."
Lord Watson was jailed by the sheriff for 16 months for his ''deliberate and dangerous'' actions.
Around 400 guests - including Scots peers and parliamentarians from Holyrood, Westminster and Europe, political journalists and lobbyists - had attended the event but most had already left the party when the fire broke out in the ground-floor reception.
Police were called when astonished hotel staff viewed the security camera recording and spotted a kilted figure stooping close to the base of the curtain, which was ablaze moments later.
The peer ''categorically'' denied any wrongdoing but in court changed his plea to guilty.
The appointment was part of the finalised team put together by Mr Corbyn following his victory last weekend.
Former top prosecutor Keir Starmer, tipped as a future leader, joins the shadow home affairs team while Emily Thornberry returns to the frontbench less than a year after being forced to quit as shadow attorney general in a row over snobbery.
The peer behind the Labour leadership election reforms that gave thousands of supporters a vote for £3 has also been given a job.
Lord Collins will serve as a party whip and a member of the international development team in the new leader's finalised list of appointments.
The list of shadow ministers includes a number of jobs for the 2015 intake as well as MPs that were considered on the fringes of the party under previous leaders.
Mr Corbyn has also appointed some of the MPs that helped him make it on to the ballot paper, including Louise Haigh, Labour's youngest MP at 28, who joins the Cabinet Office team, and Rebecca Long-Bailey, who becomes a shadow Treasury minister.
The shadow Treasury team also includes Richard Burgon, who defied convention when being sworn in as an MP to declare that he believes the head of state should be elected.
Mr Corbyn's spokesman said: "Labour's frontbench is inclusive across the party. It also includes MPs from the recent intake and is a clear commitment to the future of the party."
The revelation follows a poll that suggested the general public overwhelmingly do not believe Mr Corbyn looks like Britain's next prime minister and a significant number of Labour supporters are ready to turn their back on the party, according to a poll.
Nearly three in four people do not think the Opposition leader looks like he will take the keys to No 10, according to research for The Independent.
Some 37% of Labour supporters at the last election are now less likely to back the party in 2020 with one in five considering voting Conservative, the OBR survey of 2,000 voters found.