SNP MP Martin Docherty-Hughes will use a general debate at Westminster to call for Mr Johal’s immediate release, saying the legal case around his arbitrary detention is now beyond doubt.
Mr Johal was detained under India’s anti-terrorism laws following his arrest, accused of helping fund a Sikh-on-Hindu assassination plot – something he strongly denies.
He was snatched from the street by plain-clothes officers while shopping with his wife in India's Punjab region in 2017.
In November, Richard Ratcliffe, the husband of Nazanin Zaghari-Ratcliffe, accused the UK Government of “collusion” over Mr Johal’s situation. He and his wife were among dozens of protesters who gathered opposite Downing Street on the fifth anniversary of Mr Johal’s arrest.
The UN Working Group on Arbitrary Detention has determined Mr Johal’s detention "lacks legal basis", was based on “discriminatory grounds” owing to his Sikh faith and his “status as a human rights defender”, and that he was “subjected to torture”.
Mr Docherty-Hughes said while former prime minister Boris Johnson had previously acknowledged Mr Johal’s arbitrary detention, and successor Liz Truss met with the family last year, Rishi Sunak has yet to reach out since becoming the leader of the Conservative Party.
“My constituent Jagtar’s case is turning into one of the most prominent miscarriages of justice of our time,” he said. “After five years of incarceration in India without trial, believed tortured, this young Scot from Dumbarton is at risk of facing the death penalty.
“The UN Working Group on Arbitrary Detention has made clear that Jagtar’s detention ‘lacks legal basis’ and that he has been ‘subjected to torture’.
“This cannot continue. The UK Government needs to catch up with the legal consensus and urgently change its strategy.”
Mr Docherty-Hughes added: “We witnessed first-hand, through the case of Nazanin Zaghari-Ratcliffe and Anoosheh Ashoori, that the UK Government can bring their people home. We must see a similar approach with Mr Johal.
“Jagtar Singh Johal and his family have suffered for too long – it is time to bring him home.”
The UK Government said the UK Minister for South Asia, Lord Ahmad of Wimbledon, regularly raises this case with his Indian counterparts - most recently in October - while consular staff visit Mr Johal in prison in India to check on his welfare.
An spokesperson for the Foreign, Commonwealth and Development Office said: “We have consistently raised our concerns about Mr Johal’s case directly with the Government of India, including his allegations of torture and his right to a fair trial - we are committed to doing what we can to assist him. The Foreign Secretary visited India and raised his case with External Affairs Minister Jaishankar on 29 October 2022.
“The UK strongly opposes the death penalty in all circumstances as a matter of principle and we will continue to make this clear to the Government of India.”