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  • Writer's pictureBlair Goss

What Is Diminished Capacity in California, and How Is It Different from Insanity?

The diminished capacity defense is used in cases where the perpetrator had a mental disorder at the time that the crime was committed. According to the California Penal Code, a defendant is allowed to submit psychiatric evidence of a mental disease that will be taken into consideration when determining their punishment for a particular crime.

This article will delve into the nuances of diminished capacity, beginning with a definition of this legal term and how it differs from the insanity defense. Goss Law can also explain what is meant by caveat emptor.

What Is Diminished Capacity in California?

What Is Diminished Capacity in California?

In California, diminished capacity is not a defense that can be used itself but rather an aggravating factor that might be considered when determining an offender's sentence. Section 28 of the California Penal Code serves as the legal underpinning for diminished capacity.

It permits the presentation of evidence relating to a defendant's psychological state when the crime occurred, which may have an impact on their criminal liability.

The truth is that diminished capacity can appear similar to insanity, but the two are not the same. Insanity addresses the accused person's mental state during the trial, calling into question their capacity to grasp the charges.

Diminished capacity, on the other hand, has to do with the accused's mental condition at the time of the offense.

General Intent Crimes vs. Specific Intent Crimes

The truth is that diminished capacity can have different consequences for general intent and specific intent crimes. Proof of diminished capacity may mitigate guilt in general intent offenses by calling into question the offender's understanding or decision-making abilities during the act.

With regard to specific intent offenses requiring a particular state of mind, diminished capacity can be a more powerful defense, potentially compromising the prosecution's ability to show the required intent.

The impact of this principle can often be measured by whether it casts doubt on the offender's capacity to develop the specific motive required for the alleged crime, altering the legal approaches used in defense for both types of charges.

Expert Witness Testimony Is Often Crucial to the Success of Any Diminished Capacity Plea

It's important to understand that proving diminished capacity has a lot to do with the testimonies of medical experts. These individuals will assess the offender to determine whether they have any existing mental health conditions.

Their assessments typically look at things like the person's cognitive abilities, emotional state, and reaction to perceived threats.

The testimony of these health experts can be pivotal in any diminished capacity defense, so often, the first thing an attorney will do is hire one of these professionals to conduct a mental health evaluation and present their findings at the trial.

The History of California's Diminished Capacity Defense

California's attitude to reduced capacity has shifted over time. In the past, the state regarded the argument of diminished capacity as a full justification for a crime. This means that it allowed offenders with mental disorders to avoid criminal responsibility altogether if a serious impairment in their mental health could be established.

People v. Conley

People v. Conley (1966), an important case in California's legal history, changed this. The court ruled that diminished capacity could only be utilized to reduce a first-degree voluntary manslaughter charge to a second-degree murder charge instead of being used to relinquish the accused from liability.

This ruling was a pivotal moment, highlighting the significance of taking mental health difficulties into account but also restricting the extent to which they may free an offender of criminal charges. 

Proposition 8

In addition, California's history of diminished capacity took a dramatic turn in 1982 when voters overwhelmingly approved Proposition 8. This watershed moment signaled a change in the state's policy regarding criminal justice.

Proposition 8 added Section 28 to the California Constitution, which clearly addresses the use of diminished capacity as a legal defense. Unless specifically stated by legislation, proof demonstrating a mental impairment, defect, or disease could not be used as an excuse for or to eliminate criminal liability, according to the amendment to the constitution.

What Happens When a Person Is Proved to Have Had a Mental Defect When Committing a Specific Intent Crime?

When a judge accepts diminished capacity as a qualifying variable, it might have an impact on the trial's sentencing process. While it does not exonerate the offender from criminal liability, it can result in a less severe penalty.

An offender's sentence will likely also include psychiatric therapy or a less severe prison sentence. However, the nature of the sentence will be decided by the court on a case-by-case basis.

The Role an Attorney Plays in Diminished Capacity

The Role an Attorney Plays in Diminished Capacity

When a defendant faces criminal charges because of a criminal act that took place because of a mental impairment, an attorney can be invaluable in proving diminished capacity in trial court.

By investigating the case, approaching expert witnesses, and more, an attorney can ensure that adequate proof is presented to lessen the severity of the charges that the person faces.

Goss Law Sacramento criminal defense attorneys can guide a defendant through the legal processes and help them understand the legal framework better. They will hire the relevant experts to conduct assessments to strengthen the diminished capacity defense. This can improve the defendant's chances of securing a more favorable outcome.

Final Thoughts

Diminished capacity is a legal principle that allows the accused to present evidence of a mental defect or illness that caused a lapse in their judgment, resulting in the crime. Over the history of California's legal landscape, this common law principle has changed.

Today, it aims to strike a good balance between punishing a perpetrator for a crime and understanding the impact poor mental health can have on an individual.

Those who face criminal charges for general or specific intent crimes can present a robust diminished actuality defense and prove mental illness with the help of a reliable attorney. Goss Law has been representing and defending clients in a similar position for many years, and those being accused can turn to the firm's expertise for guidance.


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