A man who drowned his wife in a lake after 16 years of marriage has been detained indefinitely under the Mental Health Act.
Ruth Jacobs, 60, was found dead at the Needham Lake beauty spot near Needham Market, Suffolk, in February last year.
A post-mortem examination found that she had drowned.
Her husband, Stephen Jacobs, was arrested the same day and was detained under mental health legislation.
Jacobs, 60, of Spinner Close, Ipswich, was originally charged with murder but later pleaded guilty at Ipswich Crown Court to manslaughter with diminished responsibility.
Today Judge John Devaux made Jacobs the subject of a hospital order under section 37 of the act but said he did not believe it was necessary to attach a section 41 restriction order for public protection.
This means he will be held indefinitely at a medium-secure psychiatric unit.
The judge said: "Your wife died by drowning in shallow water. You admitted pushing her in knowing she could not swim."
He added it was clear Jacobs suffered from a "serious psychiatric disorder" but was unlikely to pose a risk to the public unless he formed a new relationship with a vulnerable person.
Michael Crimp, prosecuting, said the couple had lived together in Ipswich for 24 years and were married 16 years ago.
Mrs Jacobs had arthritis which affected her mobility and her husband was her full time carer, he added.
After his arrest Jacobs told police: "We drove to Needham Market to the lake and she kept following me. She always followed me like a sheep so I pushed her in."
Mrs Jacobs' two grown up children from a previous relationship were not in court for the sentencing.
Detective Chief Inspector John Brocklebank, who led the investigation, said: "Ruth's death was a tragic crime and our sympathies remain with her family and friends.
"Crimes of this severity remain a rare occurrence in Suffolk but inevitably cause concern in the local community.
"This particular case was an isolated and contained incident involving a husband and wife, with no threat to the wider community.
"Nevertheless, it resulted in a lengthy investigation by the Norfolk and Suffolk joint major investigation team and I would like to thank all the staff who contributed to this inquiry."