The Tipping Point + Freakonomics re: crime

[kurosh]

Freakonomics says crime dropped in NY from the 1980s-1990s because of abortions.

The Tipping Point says crime dropped in the same time period because they cracked down on lesser offenses. Freakonomics addresses this point specifically and says it was a minor reason.

Does anyone have more knowledge on this or an educated opinion on which might be more true?