I believe it has to do a lot with crime being reported as well. Kerala is not more crime-prone than other Indian states, people simply are more educated and civilized, and report more crimes than other states I think.
Another similar thing is Delhi being called the rape capital in India. Instances of sexual harassment are reported more in Delhi compared to other cities/small towns, because the women are more educated and empowered. Does anyone actually think that more rape and sexual harassments happen in Delhi compared to say cities like Patna, Bihar/Lucknow, UP or other smaller villages in India? Delhi has one of the best per capita incomes in the country, it makes no sense, I have seen women in Delhi wear short skirts and go around in bars and clubs at midnight on Friday/Saturday, something which women in villages can not even dream about. Women in small towns would rather keep their rape a secret and not report it to police than report to police and go through shame and be considered rape victims. Same thing happens with Kerala.
Statistics related to crime only tell part of the story, and especially in third world undeveloped or developing nations, crimes are often not reported because of backward or illogical reasons.
