Jail and inmate records give information about current, and sometimes past, inmate status. In most states, there is a department of corrections that keeps inmate databases and these are often searchable statewide online by inmate name. In instances where online searching is not available, inmate information may be obtained by contacting the sheriff's office or the state Department of Corrections.
You can call the department that arrested him/her and ask what their charges are only is they are in custody. If they have already been released or were only written a ticket, they won't release that information to you.
You can go on the Internet and find out usually like in L.A i can log on to lasd.org or you can call the sheriffs department that has your friend and ask to speak to the bailiff and they can give you that info.