A judge in Colorado is expected to decide on Wednesday whether the man accused of killing three people and wounding nine others in a shooting rampage last year at a Planned Parenthood clinic is mentally fit to stand trial.

A ruling that the defendant, Robert Lewis Dear, 58, is legally incompetent would effectively mean a suspension in criminal proceedings stemming from the first fatal attack on a U.S. abortion provider since 2009.

Two state psychologists who have evaluated Dear testified during hearings last month and on Tuesday that Dear suffers from a psychotic delusional disorder which renders him unfit to face prosecution.

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Under prosecution questioning on Tuesday, psychologist B. Thomas Gray insisted that while Dear is capable of understanding the proceedings against him, he is irrational and thus fails to meet the second test of legal competency: the ability to assist in his own defense.

Separately, defense lawyer Dan King mentioned having learned that his client had smeared himself with his own excrement and drank his own urine from a toilet because he believed the jail was poisoning his drinking water.

El Paso County Judge Gilbert Martinez said he would take the arguments of both sides under submission and issue a decision from the bench on Wednesday afternoon.

If Martinez rules Dear unfit, the defendant will be sent back to a state hospital where doctors will seek to restore him to competency.

Martinez ordered Dear's mental evaluation in December after the South Carolina native insisted on firing his attorney and representing himself.

Dear, who says he is competent, declared himself guilty and a "warrior for the babies" in a separate courtroom outburst earlier that month.

Dear has been held without bond since surrendering at the end of a bloody five-hour siege on Nov. 27 at the Planned Parenthood center, where police said he opened fire outside the building then stormed inside.

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Among those killed were a U.S. Army veteran and a mother of two who happened to be in the waiting area, and a police officer.

Dear has not formally entered a plea. Prosecutors have yet to say whether they would seek the death penalty if he were convicted.