Re: passive night vision detector?
I'd suggest that any aggressive counter measures may bring more problems than they solve. A silent, passive approach has its better points. The nail that stands up gets the hammer, and there are a lot of hammers at work along the border. Some work within the law, some don't. Don't be <span style="font-style: italic">that</span> guy.
If contacting state or county resources have issues that make them less attractive, consider opening a dialogue with Federal Border Control Agencies.
In any case, it could help to provide some form of solid intel to back up your request for law enforecement assistance.
If I were LE, I believe I would be suspicious of unsolicited, uncoordinated private efforts to assist official law enforcement agencies in their work.
Their issues and goals usually go beyond your individual wishes.
Keep in mind that not everybody who's running around the borderland in the dark are bad guys. Nasty surprises may hurt an ally, and/or bring a <span style="text-decoration: line-through">nasty</span> lethal or legal backlash.
Greg