A broad base of knowledge is critically important to our ability to investigate terrorism.

I think one of the biggest scams in law enforcement is the monitor.

When I had the job of police commissioner, 20 years ago, I was more sensitive, more cognizant of complaints and concerned about public opinion. I've learned to do what I think is the right thing. That lessens the impact of criticism. You get used to a pressurized environment and expect it every day.

Good news is not news. Bad news sells. Confrontation sells. And that's what the press is always looking for. I'm not bragging, but I have the highest job-approval rating of any public official in the city. And I've had it consistently. The approval rating for the police department is 70 percent. This notion that stop-and-frisk has torn the community apart is false.

Protecting the city is my job, which doesn't translate into hatred. This is war, and in most wars, professional soldiers don't hate the enemy. Hatred can blind you in ways that mar your judgment.

If you go into any department store these days, your picture is probably taken 30 times. In London there are 500,000 cameras in public spaces. You have no expectation of privacy in public spaces.

A broad base of knowledge is critically important to our ability to investigate terrorism.