As a general rule, criminal court records are public. That means anyone can go to the local courthouse and find out if someone's ever been arrested for, charged with or convicted of a crime. In some states, though, there are ways to hide or even destroy a criminal record, so that almost no one can find out about an arrest or conviction.
The terms "expungement" and "sealing" are often used interchangeably when it comes to criminal records, but there are some differences. "Sealing" a criminal record is when a court file is hidden from the general public. "Expunging" a criminal record means that the record is completely destroyed; it's as if the crime never happened. In essence, they're the same thing: There are very limited circumstances when a sealed record may be looked at or when the defendant (the person arrested or convicted) has to tell someone that he has a prior arrest or conviction that's been expunged.
The states have very different laws about sealing and expunging records. Some states don't allow any records to be sealed or expunged. Some allow one or both, but they don't allow either one for some crimes, like murder, kidnapping and sex-related crimes.
Below are the laws in California that deal with expunging, sealing or otherwise destroying or concealing criminal records. They may change at any time, so be sure to check the current laws for any changes. And the process itself is usually complicated. If you have any questions, an experienced criminal law attorney can give you the help and expertise you need.
Note: To see the code sections noted below, scroll through the page provided, or use the "find" feature in browser (CTRL+F) using the code section number as the search term.