The US Government Law Enforcement agencies now insist that all firewalls, software and hardware, allow access to bypass them inbound. The firewall manufacturers are obliged to supply a "key" to this effect. Britain, among other countries, has given in to this request.
The Patriot Act gives the US Government the right to plant "spyware" in anybody's computer. This can be easily checked by reading the new Spyware Act, which specifically exempts the Law Enforcement Agencies from this Law, and specifically for this purpose.