Online “smears” against Labour’s candidate in Bradford West are being investigated as possible breaches of electoral law – amid an increasingly acrimonious local constituency campaign.

West Yorkshire Police is investigating after allegations were made about Naz Shah on an anonymous website, The Independent can reveal.

Under the Representation of the People Act 1983 it is illegal to make or publish a false statement about a candidate’s personal character or conduct.

Detective Chief Inspector Jonathan Blackwell, from Bradford District Police, said: “Police have been made aware of a website containing details about an election candidate in Bradford and the matter is currently being investigated.”

With three weeks to polling day, the campaign in Bradford West is being dominated by increasingly rancorous exchanges between Respect and Labour supporters. The Respect candidate is George Galloway, who has held the seat for three years.

Naz Shah, Labour's candidate for Bradford West (BBC)

The website being investigated by police is not connected with Mr Galloway or Respect, and a spokesman for Mr Galloway said he was unaware of its contents.

Ms Shah launched her campaign detailing her forced marriage at 15 in Pakistan and sexual abuse. She also revealed that her mother had served jail time for murdering her abusive partner.

The Labour candidate left her husband in 1992, and became active in politics after her mother’s imprisonment. But at a hustings last week, Mr Galloway held up a copy of Ms Shah’s marriage certificate and asserted that she was actually at 16 and a half at the time of her marriage.

He also alleged that she has “only a passing acquaintance with the truth”, and claimed her mother had been present at her marriage. In response, it has been reported that Ms Shah “utterly refuted the allegations and said she had the documentation to prove it”.

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And one of Ms Shah’s supporters claimed agents acting on the Respect politician’s behalf pretended to be her dead father to obtain the certificate in Pakistan. Mr Galloway’s office vehemently denied this and said it had been obtained from a member of the family.

According to the Respect party website, Mr Galloway wants Ms Shah charged with perjury over evidence she gave to her mother’s murder trial and subsequent appeal. On the Respect website, Mr Galloway is quoted as saying that Ms Shah was a “disreputable candidate”.

Ratna Lachman, a human rights campaigner who chaired the hustings, said the recent events highlighted how personality rather than issue-based politics have dominated Bradford West.

She said Ms Shah’s decision to launch her campaign with a very personal account of her life rather – rather than her policies – had “left most Bradfordians perplexed”. But Mr Galloway’s attack on Ms Shah had since made many voters believe the boundaries of fair political play have been crossed, she added. Mr Galloway is defending a majority of 10,140 following a by-election in 2012.

Mr Galloway’s treatment of Ms Shah was described as “absolutely appalling” by the Labour MEP for Yorkshire and Humber, Richard Corbett.

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