Wired notes:

James Duane, a professor at Regent Law School and former defense attorney, notes in his excellent lecture on why it is never a good idea to talk to the police:

Estimates of the current size of the body of federal criminal law vary. It has been reported that the Congressional Research Service cannot even count the current number of federal crimes. These laws are scattered in over 50 titles of the United States Code, encompassing roughly 27,000 pages. Worse yet, the statutory code sections often incorporate, by reference, the provisions and sanctions of administrative regulations promulgated by various regulatory agencies under congressional authorization. Estimates of how many such regulations exist are even less well settled, but the ABA thinks there are ”nearly 10,000.”