Darren McKie, 43, admitted the manslaughter of his wife Leanne during the trial at Chester Crown Court but on Friday, March 23, he was convicted of murder.
The jury had heard she had found out he had applied for a £54,000 (US$61,900) joint loan without her knowledge.
On the day of the murder McKie left work at Stretford police station in Manchester after his wife angrily texted him, calling him a "liar" and saying she had discovered the loan application.
"What produced the argument that led to her death was that he'd been found out in committing serious criminal offences," said prosecutor Nigel Power QC.
The body of the 39-year-old detective constable was found in Poynton Lake in Cheshire on September 29 last year. She had been strangled.
Husband and Father Continued Charade After Murder
After killing his wife McKie continued with his normal daily routine but after he put his children to bed he sneaked out and dumped his wife's body in the lake before disposing of her car.
At one point he texted her phone, pretending to be an innocent and unaware of her fate.
"Hi hun. Your dad text me. They have not heard from you. You OK? Bit worried now. xx," McKie texted as her body lay face down at the bottom of the lake.
He was confronted by a police patrol as he walked home in the dark.
The officers, who were keeping an eye out for burglars, asked him what he was doing in the area but they let him go when he said he was close to home. But he was actually three miles from his home and after the patrol drove off he dumped his bloody sneakers in a wheelie bin.
The couple, who had three children, had financial problems and owed more than £100,000 ($114,600).
'Perfect Family' Had Secret Money Problems
Mr. Power said they professed to be a "perfect family" but were living "well beyond their means."
McKie owed the builders working on the house £60,000 ($68,700) and had maxed out his credit cards.
They had just moved into a £435,000 ($498,000) house in Wilmslow, an affluent town in Cheshire which is popular with footballers, and were spending money on extending and renovating it.
McKie, who had been with Greater Manchester Police for 20 years, had forged his wife's signature, using her warrant number and hacked into her police email in order to obtain her payslips for the loan application.
A post mortem report found McKie had broken two bones in his wife's neck when he strangled her.
After changing his plea to guilty to manslaughter during the trial McKie tried to claim his wife had died accidentally during a struggle.
He will be sentenced on Tuesday, March 27, but the mandatory sentence for murder is life imprisonment.