A 12.5-year-old piece by Glenn Reynolds. It was true then and it's true now.
The United States Code -- containing federal statutory law -- is more than 50,000 pages long and comprises 40 volumes. The Code of Federal Regulations, which indexes administrative rules, is 161,117pages long and composes226volumes.
No one on Earth understands them all, and the potential interaction among all the different rules would choke a supercomputer. This means, of course, that when Congress changes the law, it not only can't be aware of all the real-world complications it's producing, it can't even understand the legal and regulatory implications of what it's doing.