The jury took several days to return the verdict, finding Beckett guilty of first degree murder.
Sentencing took place immediately, Beckett receiving 25 years' imprisonment with no possibility of parole.
The 60-year-old stood trial at the British Columbia Supreme Court in Kelowna charged with the murder of his second wife, Canadian school teacher Laura Letts-Beckett.
She died on August 18, 2010, while the couple were boating in a small inflatable vessel on Upper Arrow Lake, northeast of Vancouver.
Her death was initially reported as a drowning, Beckett claiming she accidentally fell from the boat; however, he was arrested one year after the death and his trial for murder began on August 21.
Raised in Hastings, Beckett was running a tour business taking groups from Napier to Cape Kidnappers when he became a Napier councillor in 1998. He did seek re-election and moved to Canada, where he met and married the then Ms Letts.