> So we're not catching "real" spies and terrorists; we're catching nannies trying to get paid under the table; do you think maybe we've got bigger fish to fry? This is a bad precedent, and what are we gaining? Nothing.
A country which controls its borders gains … control of its borders. If it's illegal to enter a country as a tourist in order to live with one's girlfriend, well it's illegal to enter that country as a tourist in order to live with one's girlfriend. That doesn't mean the law is right, or good, or desirable, just that if one enters that country as a tourist in order to live with one's girlfriend, one will be breaking that country's law and is liable to be deported.
Although I tend to favour open borders, myself, I think it's perfectly reasonable for the customs police of any country to turn away people trying to enter that country illegally.
That doesn't address the question of balance between the seriousness of the illegality and the invasiveness of the investigatory technique.
It would certainly be feasible to require every vehicle to be fitted with a data/position logger so that a vast number of hitherto undetected breaches of the laws governing the road can be immediately detected and punished - but it's pretty clear that the invasiveness of this is not worth the gains in compliance.
A country which controls its borders gains … control of its borders. If it's illegal to enter a country as a tourist in order to live with one's girlfriend, well it's illegal to enter that country as a tourist in order to live with one's girlfriend. That doesn't mean the law is right, or good, or desirable, just that if one enters that country as a tourist in order to live with one's girlfriend, one will be breaking that country's law and is liable to be deported.
Although I tend to favour open borders, myself, I think it's perfectly reasonable for the customs police of any country to turn away people trying to enter that country illegally.