This is not actually the stupid question that it at first looks like to most normal people. I'll clarify though, to get to the real point.
Many conservatives have argued over the last few years that techniques such as waterboarding are amazingly good techniques for getting reliable information out of terrorist suspects. So why don't America's police forces waterboard? What would you say if you found out that your local PD was waterboarding criminal suspects?
If it's such a great tool for information gathering, how can anyone argue with local law enforcement using it to solve the types of crime that impact all of us? Terrorism, after all, really only affects the few in the US. If you live in a rural community, the odds of an attack directly impacting you are low. Even in the city of New York, in the most spectacular terrorist event in history, fewer than 3,000 people out of more than 8 million lost their lives (18 million if you include the "metro" area for New York City).
Crime though... jeeze, everyone's been a victim of crime at one time or another. When I was a teenager, my car stereo was stolen. As an adult, I once interrupted a burglary at a friend's home. In neither case was a suspect ever apprehended. I can only imagine how many suspects would have confessed to both crimes if local cops had used waterboarding! So why not?