Government policies for flying with a Kirpan
Law in the United States
From 2016, the TSA has clearly prohibited in carrying "religious knives and swords" longer than 2.5 inches on oneself or in their carry-on baggage and requires that they are packed in checked baggage.
Law in the United Kingdom
Having a kirpan without a good reason in a public place would be unlawful under section 139 of the Criminal Justice Act 1988. However, there is a defence for an individual to prove that he carries it for "religious reasons".
Law in Scotland
Section 49 of the Criminal Law (Scotland) Act 1995 makes it illegal to go into a public place with a blade or pointed article. A defence exists under section 49(5)(b) of the act for pointed or bladed articles carried for religious reasons.
Law in Sweden
Swedish law has banned weapons in public places that also includes knives. However, carrying folding pocket knives is permitted.
Law in India
Sikhs are allowed to carry the kirpan onboard domestic flights in India. The full length of the Kirpan shouldn't exceed 23 cm (9 inches) long and the length of the blade shouldn't exceed 15 cm (6 inches) long.
Law in Canada
Kirpans are allowed in almost all public places in Canada, but there have been some court cases regarding carrying kirpans on school premises. From November 2017, Transport Canada has updated its Prohibited Items list to allow Sikhs to carry kirpans smaller than 6 cm on all domestic and international flights except to the USA however.
Law in Denmark
On October 2006, the Eastern High Court of Denmark upheld the law of a Sikh carrying a kirpan was illegal, making it become the first country in the world to pass such a ruling. Danish law permits carrying of knives which can be longer than six centimetres in public places including work-related and recreation. The High Court didn't find religion to be a good reason for holding a knife.