Maybe he buried himself?

Stuff reports:

A woman has pleaded not guilty to murdering her partner weeks before his body was found buried in his backyard.

Kitchen hand Rena Maloney appeared in the High Court at Christchurch on Friday charged with murdering Martin Orme Berry, 55, on December 29.

His body was found in the backyard of his property on Main North Rd, Papanui, about two weeks later.

I guess it is possible he dug the hole himself, jumped in and shoveled dirt over himself – but pretty un;ikely!