The Manhattan DA is a real problem here. Insists on prosecuting people for knives that plainly do not fit the definition described in the statute as illegal (one hand openers for instance). Fortunately, the courts appear to be interpreting the law as written. So, you will eventually win in court, but you will pay big bucks and waste a lot of time.

The NYPD officers I have seen who encounter knife carrying citizens have been pretty common sense. (Don't clip your folder inside your pocket so the clip shows.) IF the knife is legal, they will usually issue a stern warning, make you put it in your pocket and send you on your way. I witnesses a cop let a guy with a one hand opener slide, but I have heard several accounts of people being arrested for the same type of knife.

I even had one cop hold my SAK for me when I had to go into 1 Police Plaza (police headquarters) and forgot to leave it at the office. He may have been the exception rather than the rule.

That doesn't mean that a cop having a bad day, or behind on his arrest quota (that of course, doesn't exist) won't make your life hell.

Bottom line, keep it in your pocket.