He was not murdered... I was stationed at Mannheim Germany and Have seen the plaque where his accident happened. Speyer is 25 km (16 miles) south of Ludwigshafen and Mannheim.
On December 8, 1945, Patton's chief of staff, Major General Hobart Gay, invited him on a pheasant hunting trip near Speyer to lift his spirits. Observing derelict cars along the side of the road, Patton said, "How awful war is. Think of the waste." Moments later his car collided with an American army truck at low speed.
Gay and others were only slightly injured, but Patton hit his head on the glass partition in the back seat. He began bleeding from a gash to the head and complained that he was paralyzed and having trouble breathing. Taken to a hospital in Heidelberg, Patton was discovered to have a compression fracture and dislocation of the cervical third and fourth vertebrae, resulting in a broken neck and cervical spinal cord injury that rendered him paralyzed from the neck down.
Patton, who had been told he had no chance to ever again ride a horse or resume normal life, at one point commented, "This is a hell of a way to die." He died in his sleep of pulmonary edema and congestive heart failure at about 18:00 on December 21, 1945. Patton was buried at the Luxembourg American Cemetery and Memorial in the Hamm district of Luxembourg City, alongside wartime casualties of the Third Army, per his request to "be buried with [his] men".