Would you hire an ex-convict? Would you work with one?
Of course, the problem with staying mum about your trouble is that the boss may still find out -- and do you want him to hear the news from you or the office gossip?
Even if you do decide to come clean, don't post it on Facebook or blab about it in the break room. In some cases, whatever you say to someone else can be used in your trial and possibly seen as an admission of guilt, depending on what you spill to others.
One bit of hope you can hang onto if you're arrested is that if you're a valuable employee, the boss may be more tolerant of your legal problems and be willing to give you a second chance.
The boss also may be more tolerant of an arrest if it just involves poor judgment on your part -- such as being caught peeing in an alley after a Super Bowl party -- rather than smacking your roommate over the head with a lava lamp. Charges of violence can make employers nervous, not to mention fellow employees.
How would you feel working with someone with a criminal record?