Historically, legal authority to issue passports is founded on the exercise of each country's executive discretion (or Crown prerogative). Certain legal tenets follow, namely: first, passports are issued in the name of the state; second, no person has a legal right to be issued a passport; third, each country's government, in exercising its executive discretion, has complete and unfettered discretion to refuse to issue or to revoke a passport; and fourth, that the latter discretion is not subject to judicial review. However, legal scholars including A.J. Arkelian have argued that evolutions in both the constitutional law of democratic countries and the international law applicable to all countries now render those historical tenets both obsolete and unlawful.
Under some circumstances some countries allow people to hold more than one passport document. This may apply, for example, to people who travel a lot on business, and may need to have, say, a passport to travel on while another is awaiting a visa for another country. The UK for example may issue a second passport if the applicant can show a need and supporting documentation, such as a letter from an employer.
National Conditions of Passport
Today, most countries issue individual passports to applying citizens, including children, with only a few still issuing family passports (see below under "Types") or including children on a parent's passport (most countries having switched to individual passports in the early to mid-20th century). When passport holders apply for a new passport (commonly, due to expiration of the previous passport, insufficient validity for entry to some countries or lack of blank pages), they may be required to surrender the old passport for invalidation. In some circumstances an expired passport is not required to be surrendered or invalidated (for example, if it contains an unexpired visa).
Under the law of most countries, passports are government property, and may be limited or revoked at any time, usually on specified grounds, and possibly subject to judicial review. In many countries, surrender of one's passport is a condition of granting bail in lieu of imprisonment for a pending criminal trial due to flight risk.
Each country sets its own conditions for the issue of passports. For example, Pakistan requires applicants to be interviewed before a Pakistani passport will be granted. When applying for a passport or a national ID card, all Pakistanis are required to sign an oath declaring Mirza Ghulam Ahmad to be an impostor prophet and all Ahmadis to be non-Muslims.
Some countries limit the issuance of passports, where incoming and outgoing international travels are highly regulated, such as North Korea, where ordinary passports are the privilege of a very small number of people trusted by the government. Other countries put requirements on some citizens in order to be granted passports, such as Finland, where male citizens aged 18–30 years must prove that they have completed, or are exempt from, their obligatory military service to be granted an unrestricted passport; otherwise a passport is issued valid only until the end of their 28th year, to ensure that they return to carry out military service. Other countries with obligatory military service, such as South Korea and Syria, have similar requirements, e.g. South Korean passport and Syrian passport.
Passport National Status
Passports contain a statement of the nationality of the holder. In most countries, only one class of nationality exists, and only one type of ordinary passport is issued. However, several types of exceptions exist:
Multiple classes of nationality in a single country
The United Kingdom has a number of classes of United Kingdom nationality due to its colonial history. As a result, the UK issues various passports which are similar in appearance but representative of different nationality statuses which, in turn, has caused foreign governments to subject holders of different UK passports to different entry requirements.
Multiple types of passports, one nationality
The People's Republic of China (PRC) authorizes its Special Administrative Regions of Hong Kong and Macau to issue passports to their permanent residents with Chinese nationality under the "one country, two systems" arrangement. Visa policies imposed by foreign authorities on Hong Kong and Macau permanent residents holding such passports are different from those holding ordinary passports of the People's Republic of China. A Hong Kong Special Administrative Region passport (HKSAR passport) permits visa-free access to many more countries than ordinary PRC passports.
The three constituent countries of the Danish Realm have a common nationality. Denmark proper is a member of the European Union, but Greenland and Faroe Islands are not. Danish citizens residing in Greenland or Faroe Islands can choose between holding a Danish EU passport and a Greenlandic or Faroese non-EU Danish passport.Passports have a limited validity
Passports validity, usually between 5 and 10 years.
any countries require passports to be valid for a minimum of six months beyond the planned date of departure, as well as having at least two to four blank pages. It is recommended that a passport be valid for at least six months from the departure date as many airlines deny boarding to passengers whose passport has a shorter expiry date, even if the destination country does not have such a requirement for incoming visitors.