I will be the first responsible one to say that the .30-06 is an EXTREMELY POOR CHOICE for a civilian law enforcement rifle!!!
.30cal rounds will always have a tremendous over-penetration problem especially when compared to the .223's tendency to fragment in flesh and/or building materials. .30cal is very likely to go through the perp, through the wall behind him, and through three or four bystanders. Even most soft-point .30cal rounds still carry absolutely devistating energy and sectional-density and thus over-penetrate.
This will always present a hazard when given the bounds of civilian service. The M14, M1 Garand, FAL, etc. are all generally POOR choices for a partol or home-defense rifle.
Bottom line: A firearm using the .223 cartridge is hardly a toy, but it's combination of speed, penetration, and fragmentation limiting OVER-penetration, render it a far far superior choice for CIVILIAN use of all sorts.