TULSA, OK (AP) - Tulsa police say they accidentally destroyed the alleged murder weapon in the case of an Oklahoma man who is to be retried for the death of a Tulsa couple.

The Tulsa World reports the missing evidence could allow Phillip Anthony Summers to avoid the death penalty.

Officer Jason Willingham says an internal investigation found the gun allegedly used in the shooting death of Shelly and Ples Vann. Jr. had been mistakenly destroyed because of a clerical error.

Summers was originally sentenced to death but the Oklahoma Court of Criminal Appeals ordered a new trial. The court concluded that Summers should have been able to present testimony about an alternative perpetrator.

Prosecutor Tim Harris says the gun's destruction makes it difficult for his office to seek the death penalty.

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