I remember the Franco era quite well, having begun visiting spain regularly in 1956. Yes, there was crime then but it was of a different nature. Most crimes, as has been suggested, were crimes of stealth. Street crime was rare.

Attacks on tourists, which Franco was eager to attract, were non-existent. At least I never heard of any back then. One reason was that the guardias were judge, jury and sometimes executioner. A mugger could get himself shot. I recall a case where a thief on a Vespa snatched a purse. The quardia brought him down with his rifle. That sort of thing does tend to discourage repetition.