A Sikh would not condone the killing of his child to preserve family honour, the Old Bailey has heard.
Kalvinder Dosanjh denies three charges of soliciting murder
Pc Kalvinder Singh, who advises police on cases involving the religion, said true believers would not attempt to carry out "honour killings".
He was giving evidence in the case of Kalvinder Dosanjh, who is accused of hiring a hitman to kill his daughter.
Mr Dosanjh, 51, Rochester, Kent, denies three charges of soliciting murder and firearms charges.
It is claimed that Mr Dosanjh, a devout Sikh, felt disgraced after his daughter Sanjit, 23, moved in with her Jewish boyfriend, Temple Jazac, 43.
In earlier evidence, the Old Bailey was told how a man approached by Mr Dosanjh to kill his daughter was an undercover policeman.
Mr Dosanjh is also alleged to have wanted to kill Mr Jazac, as well as Malcolm Calver, a man he mistook for Mr Jazac's father, on or before 26 September last year.
On Tuesday, Pc Singh suggested that a Sikh would not be disgraced if his daughter had a relationship with someone of another religion.
"There's multiculturalism ingrained in Sikhism," he said.
However, he added that while intermarriage between Sikhs and people of other ethnic backgrounds was not unusual, "it's still frowned upon".
He claimed that Sikhs do not often intermarry in Britain because they still have not forgiven the British for ruling the Punjab area in India.
But he agreed there had never been any animosity between Sikhs and Jews.
Mr Dosanjh's alleged accomplice Jagjit Singh Rai, 53, a businessman from Goodmayes Avenue in Ilford, Essex, has already pleaded guilty to three counts of solicitation to murder and possession of a prohibited weapon.
The trial continues.