Sheriff Arpaio was convicted of a misdemeanor crime committed while in the employ of the State of Arizona, which one may note is not the same as the United States of America. Minor crimes will not affect one's pension or retirement, nor should they.
In my opinion if a government agents pension was at risk, they would think before they commit any crimes, minor or major...
Criminals are criminals no matter how minor the crime and no matter who employes said criminal..
Thank you for your opinion.