It's not just a matter of using Linux versus Windows. I get the occasional spam with poisoned executable attachments inside zipfiles. I view zipfile headers, and often see stuff like the following 2 examples...
".scr" is executable in Windows http://filext.com/file-extensi... so I assume that's a trojan-planting attempt. One possible legal defense is that it's impossible to tell whether you're blocking a trojan sent by police or by foreign criminals.