Bench warrants are issued when you do not do something that the Court has ordered you to do. For example:
Each of these examples consitutes a reason for the Court to issue a bench warrant. In addition, the Judge will also take a number of other steps, like vacating your bail, forfeiting your bail, and sometime notifying the State Department of Licensing to suspend your license.
There may be a lot of good reasons why you did not appear, attend or complete the requirement set on you. The problem is, at the time the warrant is issued, the Judge is not informed about the reason you have not complied, just that you have not done what you were ordered to do.
Get your documents together supporting your reasons and contact your lawyer to discuss turning yourself in ASAP.
Why Shouldn't I Just Wait for the Police To Pick Me Up?
The way cops and the courts typically look at this situation, is that the guilty flee, when the innocent stop and assert their innocence. If you were purposely trying to diss the Judge, congrats, you did. If as in most circumstances you forgot about the court date, overslept, got stuck in traffic, the baby got sick, or you have some other explanation, contact your lawyer as soon as possible. If you can get to the Court that same day, do it. If you can get to the appointment, even if you're late, do it. All efforts you make to mitigate this, can be used to support an argument that it was not intentional.
Turning yourself in, without making the cops come and find you shows the judge that you did not intend to miss the date, or other obligation. Make sure you tell the Judge that it was not intentional, and show the documents that establish where you were if you were stuck somewhere else. Talk to your lawyer as soon as you realize there is a warrant, and maybe the bail does not get taken.