(JTA) — A retired California barber was sentenced to life in prison for shooting and killing a urologist who he blamed for a botched surgery.

Stanwood Elkus, 79, was sentenced on Friday to life in prison without the possibility of parole by the same jury that had convicted him on charges of first-degree murder in late August.

Elkus shot Dr.  Ronald Gilbert, 52 and the married father of two children, in January 2013 at his practice in Newport Beach, California, two decades after Gilbert, then a medical resident at the Veterans Administration hospital in Long Beach, California, advised him to have simple urethra-widening surgery to deal with frequent urination due to a narrowing of the urethra.

Gilbert did not conduct the surgery, which left Elkus with incontinence, erectile dysfunction, and diminished sex drive. Still, Elkus blamed Gilbert for his problems.

Elkus’ attorneys used an insanity defense, claiming he suffers from dementia and depression. Elkus uses a wheelchair and is mostly deaf. The trial lasted three weeks and the jury deliberated for 40 minutes before delivering a verdict.

The day before he was murdered, Gilbert received a $30 million offer from a corporate buyer for a pharmaceutical company he started with a partner focused on treatments for sexual dysfunction, according to the Washington Post.