NORTH TEXAS (CBSDFW.COM/CNN) — Attorneys appear to be preparing an insanity plea for the Collin County man suspected of carrying out a mass shooting at an El Paso Walmart last year.

Lawyers for Patrick Crusius said he was in a psychotic state when he was taken into custody minutes after the shooting and suffers from mental disabilities.

Crusius’ defense counsel disclosed the mental health conditions in a motion filed last week that asks for more time to investigate the “red flag mitigation themes” as prosecutors decide whether to seek the death penalty.

Crusius is charged with hate crimes resulting in death, hate crimes involving an attempt to kill, use of a firearm to commit murder and in relation to a crime of violence, and use of a firearm during and in relation to a crime of violence, according to an indictment unsealed in February.

The charges relate to the people who were killed as well as those who survived the August 3 massacre — one of the nation’s deadliest shootings and the deadliest attack on Latinos in modern U.S. history.

Crusius –a native of Allen, a city about 20 miles north of Dallas — has pleaded not guilty.

His attorneys said in the motion that Crusius has been diagnosed with lifelong neurological and mental disabilities, which they described as “severe.” The accused shooter was allegedly in special education for most of his school years, the motion said.

Crusius was treated with antipsychotic medication after his arrest for the shooting, his attorneys said in the motion, citing mental health professionals at the jail where he was held.

The motion was granted by the court.

According to the motion, the US Attorney for the Western District of Texas told the defense team that if they don’t present Crusius’ mitigation by July 20, the government will make a decision regarding the death penalty without input from the defense team. In response, the motion sought to “allow reasonable time for counsel for the parties to discharge their respective duties with respect to the question of whether the death penalty should be sought.”

The motion said that more time is needed for effective counsel investigations of the “tremendous” volume of discovery.

“There are a number of ‘red-flag’ mitigation themes for counsel to investigate which require more time to investigate and develop and prepare to submit to the government, and the circumstances of this case compel a grant of more time for investigation,” the motion said.

The motion also noted that dozens of possible witnesses still need to be contacted and interviewed. “To attempt to meet with someone in person during this pandemic would not only violate the explicit and unanimous advice of national public health authorities, but also risk impairing the relationship with prospective witnesses by displaying a callous disregard for their and their families’ safety,” the motion stated.

The defense team also asked for additional time due to the COVID-19 pandemic, saying that visits from experts are currently not feasible due to restrictions and health concerns.

“Counsel must gather all of the information necessary to inform experts who will then be in a position to interview Mr. Crusius at the jail and render opinions regarding his mental status at the time of the shooting,” the motion said. “As of now, no experts can accomplish these things, as to date, they have either been under stay-at-home orders from the Government or their employers, or they are in a high-risk category for COVID and cannot travel to meet Mr. Crusius.”

According to the motion, a status conference in the case has been scheduled for October.

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