Why some countries do not extradite their own nationals

Several states bar or restrict the extradition of their own citizens, often in the constitution, and instead offer to prosecute them at home.

Article 16(2) of Germany's Basic Law says "No German may be extradited to a foreign country", with exceptions allowed by law for EU member states and international courts.¹
Article 6 of the European Convention on Extradition gives each party the right to refuse to extradite its nationals, but it must then submit the case to its own authorities for possible prosecution if asked.²
The US Justice Department notes that a fugitive may be beyond reach where the country of refuge does not extradite its nationals, and lists deportation, expulsion and foreign prosecution as alternatives.³

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