Birmingham Crown Court was told that Christine Hemming, Liberal Democrat MP John Hemming and his lover, Emily Cox, were involved in a “love triangle” at the time of the alleged offence last September.
Opening the case against Mrs Hemming, prosecutor Jason Pegg told jurors she spent three minutes inside Miss Cox’s home before emerging with the kitten under her arm.
Explaining that Mr Hemming divided his time between his marital home in Moseley, Birmingham, and the nearby residence of Miss Cox, Mr Pegg said: “This is, for want of a better word, a love triangle - a love triangle that both women are fully aware of.”
Mrs Hemming, who denies burglary, listened from the dock as Mr Pegg added: “This case is all about the defendant going to Emily Cox’s home one evening in September of last year before entering that home and stealing a kitten known as Beauty.
“At that house there are CCTV cameras, which have been installed around the house, giving coverage of the gardens.”
The court heard that Miss Cox was out at a meeting in the early evening of September 29 and returned home to find that one of her two cats, Beauty and Twinkle, was missing.
Miss Cox, who lives in Church Road, Moseley, searched the local area for the kitten during the next few days and then viewed the CCTV footage in the first week of October.
Urging jurors to be dispassionate in their consideration of the “perhaps out-of-the-ordinary” case, Mr Pegg told them: “Beauty, the kitten, was never seen again by Emily.
“CCTV footage, members of the jury, showed exactly what had happened to the cat.
“The defendant, Mrs Hemming, had sneaked around the back garden, she had opened the back door, she had entered Emily’s house and she remained in that house for three minutes or so.
“She then left the house through the same door which she had entered but, when she left the house, under her left arm was Beauty the kitten.”