Ask HN: Where to get funding for law enforcement product?

I'm based in Switzerland and I built a product (software and heavy duty bulletproof hardware) which is used by road traffic law enforcement. In order to sell it on a larger scale, I'd need to exhibit it on say, Intertraffic (trade exhibition) or similar. After bootstrapping for ~4 years, the time has come to look for external funding (type-testing and certification is a significant cost). Are there any VCs in this industry? How to find them?