Double Jeopardy when received a police caution?

Question

I was curious about the application of Double Jeopardy around the world, and in particular the European Union, in the following scenario.

Someone commits a crime in England, the police arrest them. Rather than sending them to court, the offender receives a warning, caution, or similar outcome. The matter never goes to court.

Would the offender be protected against being punished again, for the same crime and facts, in another sovereign? I cannot think of a good example, so just assume it is a crime which another country can also claim jurisdiction over, for whatever reason.

Exclude countries that do not apply Double Jeopardy protections when someone has already served a sentence in another sovereign, such as the United States of America.

Answer 1

canada

The constitutional protection against double jeopardy is found at s. 11(h) of the Charter:

Any person charged with an offence has the right... if finally acquitted of the offence, not to be tried for it again and, if finally found guilty and punished for the offence, not to be tried or punished for it again

If there was no charge, you aren't even within potential scope of the protection against double jeopardy.

Answer 2

Double jeopardy doesn’t apply to different Sovereigns

The laws of one state do not bind another- so, as in your example, if the UK declines to prosecute or even if they do and you serve 20 years, any other nation with jurisdiction can also prosecute you. The same is true of sub-national jurisdictions - if I stand in Washington and shoot someone in British Colombia, all of the state, province, and both national governments can charge me, convict me, and punish me. However, Canadian but not US law, prohibits both the province and the national government from bringing charges - it has to be one or the other.

The convention is that so long as I have been punished somewhere, most Sovereigns will not seek to punish me again, but it’s a guideline, not a rule.