The man accused of shooting trainee Pc Rachael Bown has admitted firing the shots, but denies aiming a gun at her
Trevon Thomas, 24, of Bilborough, told a jury at Nottingham Crown Court that the gun went off accidentally as he ran away from police.
Thomas, who denies attempted murder, apologised for injuring Pc Bown.
He told the court: "I'm very sorry about Miss Bown's injuries, but it was an accident. I was under the effects of the CS gas."
The 24-year-old probationary Pc was shot in the stomach while on patrol in the Lenton area of Nottingham on 14 February 2006.
She suffered life-threatening injuries when she was shot below her body armour, while investigating reports of a burglary.
The prosecution claims Mr Thomas shot Miss Bown deliberately.
But in testimony on Friday, Mr Thomas said he was blinded by CS gas fired at him by another police officer and the gun went off three times accidentally as he wiped his eyes.
He told the court he was not aiming at her.
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