Interestingly when the police suggested it was not possible for Sheila to shoot herself twice, Jeremy did not refute this. Or passionately say the police had to be wrong. Or demand proof of this.
He simply shrugged his shoulders and said perhaps it was the dog who fired the second shot. As well as claiming Neville may have said 'she' rather than 'Sheila'. Suggesting a random woman carried out the massacre. Leaving the gun on Sheila ! Ann Eaton ?
All in the Interview Transcripts & Wilkes's book.