First you should know this: Only a liscenced psychologist (PhD) or Psychiatrist (MD) is able to officially diagnose a person with any mental disorder.
Second, I am a student in psychology, so I cannot diagnose anyone and my STRONG advise is if you think you have a personality disorder, please see a psychologist! I will provide the standard diagnostic criteria for Antisocial Personality Disorder from the "Bible" of psychotherapy... the DSM IV-TR.
Diagnostic Criteria:
There is a pervasive pattern of disregard for and violation of the
rights of others occurring since age 15 years, as indicated by three
(or more) of the following:
1. failure to conform to social norms with respect to lawful behaviors
as indicated by repeatedly performing acts that are
grounds for arrest
2. deceitfulness, as indicated by repeated lying, use of aliases, or
conning others for personal profit or pleasure
3. impulsivity or failure to plan ahead
4. irritability and aggressiveness, as indicated by repeated physical
fights or assaults
5. reckless disregard for safety of self or others
6. consistent irresponsibility, as indicated by repeated failure to
sustain consistent work behavior or honor financial obligations
7. lack of remorse, as indicated by being indifferent to or rationalizing
having hurt, mistreated, or stolen from another

Again... I am not qualified to diagnose anyone. I provided this information as a guideline, but if you suspect that you or someone you know has a personality disorder, consult a professional.