A criminal background check is part of the qualifying process when you apply to rent an apartment. The other parts are rental history, employment and income verification, and credit check. The reason the criminal background check is so important is that people do not want to live in high crime areas or live next door to unsavory characters who aren't abiding by the law.
When looking at your criminal background check, an apartment manager would be most concerned by any crimes of a violent nature, whether they are felonies or misdemeanors. Any crimes that involve violence would most likely get you denied when you apply to rent an apartment.
Managers perform the background checks on various databases that are available. Unfortunately, these databases aren't always as accurate as a credit check because they aren't as regulated and if you find a mistake, it can be more difficult to get it fixed because there aren't correction procedures in place.
If you do have a crime on your record, many apartment communities will still allow you to rent if your conviction was for something non-violent and happened several years ago, usually 3, 5, 7 or 10 years. Convictions such as a DWI or DUI can even affect whether you can rent an apartment because some communities have a zero tolerance policy in regards to criminal background checks. Many communities can be quite a bit more flexible, but the fact remains that even a DWI or DUI can get you denied.
If you were convicted as a minor, it can still affect your criminal record because the State of Texas often charges juveniles as an adult. Also, if you had deferred adjudication, it is the same thing as pleading guilty in the eyes of apartment complexes. However, if you were charged, but not convicted, that will not be on your criminal record and will not affect your ability to rent an apartment.
If you have crimes on your record that you are concerned about apartment complexes seeing, a good apartment locator can help you find communities that will work with you.