The family of Surjit Singh Chokhar are to make a public appeal at the Scottish Parliament tomorrow alongside the former police officer turned MSP who was Assistant Chief Constable at the time of the case, as pressure grows on the Crown Office to reopen the unsolved murder which took place in 1998.

The text of a letter written by the family's solicitor to Lord Advocate Frank Mulholland has been released, urging him to consider instructing Strathclyde Police to launch a public appeal in partnership with the family for witnesses to come forward. A press conference tomorrow will see the family share a platform with Graeme Pearson MSP of the Justice Committee and Humza Yousaf MSP.

The letter urges the case to be reconsidered following the passage of the two trials law which allows individuals to be prosecuted again for crimes of which they have been acquitted, if "compelling" new evidence emerges.

Three men were previously tried for the murder of Chokhar, in two separate trials. No conviction was made for the crime.

"Just as in Stephen Lawrence’s case, the killers of Surjit Singh Chhokar should not rest easy in their beds," the letter to Mulholland said.

"Sir Anthony Campbell concluded there was a sufficiency of evidence of charges of murder and acting in concert against three of the accused however this did not take place. Thirteen years on the family have hope that the Crown Office will pursue justice in light of the new law on Double Jeopardy."

In December the Crown Office briefed selected media that Lhamin Khalifah Fhimah, acquitted in the Pan Am 103 trial, may face a retrial under the two trials reforms.

Earlier this year former MP Mohammad Sarwar accused the Crown Office of institutional racism, whilst in August the Crown Office were accused of legitimising racism by the family of Simon San, whose murder prompted an apology by Lothian and Borders Police for their handling of the case.

The letter to Mr Mulholland adds : "The family in the past condemned the legal system for failing them and being institutionally racist, but they appreciate that 13 years have passed and a radical overhaul in the treatment of victims and prosecution of murder cases has taken place at the Crown Office."

Yesterday afternoon the Crown Office press office released a statement that Mr Mulholland and the solicitor general "would be pleased to meet with the family". However it added that "it was too early to speculate how any particular case might be dealt with under the reformed double jeopardy law."

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