You resolve it the same way you do now. It's not like police in the UK will refuse to arrest someone who is breaking UK law because they're not a UK citizen. So

You resolve it the same way you do now. It's not like police in the UK will refuse to arrest someone who is breaking UK law because they're not a UK citizen. So citizenship already has minimal impact on selective arresting policies. Extradition is another issue, but again, it's separate from citizenship and if anything, its current implementation is the most realpolitik demonstration of practical geopolitical power, since it's constrained first and foremost by the location of an individual, regardless of their residency or citizenship status.