Fourteen states prohibit discrimination against some form of ex-offender discrimination in the workplace. Arizona, Colorado, Connecticut, Florida, Kentucky, Louisiana, Minnesota, New Mexico and Washington ban ex-offender discrimination in public employment. Five other states, Hawaii, Kansas, New York, Pennsylvania and Wisconsin, prohibit this form of job discrimination in both private and public employment.
If your friend has a state, county or municipal government job in one of the above fourteen states or a private sector job in one of the five latter states, the likelihood of his employer discharging him due to his arrest and his mug shot is remote. Moreover, such adverse action would likely be unlawful. If, however, he does not work in one of these states, then he may not have any direct protection under the law from his employer terminating his at-will employment under these circumstances.