If the murder rate would be down because of the conviction rate the other crimes would be also down like that but the percentages are not showing it at all.
Who said that the other crimes are not down?
http://www.nationmaster.com/country-info/compare/Japan/United-States/Crime
For example, the incidence of rape is 66 times lower in Japan, when compared to the US. Car theft is 20 times lower, and Assaults are 15 times lower.
You are obsessed with the us .. let it go for god sake
Seems like the conviction in japan isn't affecting kidnappings more than the one is Austria for example...
http://www.nationmaster.com/country-info/stats/Crime/Kidnappings
http://www.nationmaster.com/country-info/compare/Austria/Japan/Crime
Or the number of car thefts compared to ... Russia
.