When you're accused of a crime that you don't remember committing or that you believe you committed under the influence of drugs or another substance, you may be able to use an insanity defense. People with a history of mental illness, those who are driven to extremes because of their situations and others may have a good chance in court by using this solid defense technique.
With an insanity defense, you need to show that you did not understand what you were doing at the time of a crime. For example, if you have a relapse of a mental health condition, you may not know who you are, where you are or what you're doing when you commit a crime. On the other hand, if you knew what you were doing and chose to participate, it would be difficult to pursue an insanity defense.
Although the media makes it seem simple, an insanity defense is not the best way to get out of trouble in most situations. This works best for individuals with a history of mental illness or an incapacity to understand how their actions affect others. Other ways to use this defense would be if you could show a mental defect resulted in your actions or if you struggle with impulse control and were unable to stop yourself from committing a crime.
If you want to use an insanity defense, documentation from a medical professional or psychiatrist could help your case. Showing a true mental health disorder is just a single step in proving you weren't in the right state of mind when the crime was committed.
Source: FindLaw, "Insanity Defense," accessed Dec. 18, 2017