Motivation:
My daughters love and admire the character of Molly Bannaky and her descendant Benjamin Bannaker:
https://www.womenhistoryblog.com/2008/07/molly-welsh-banneker.html
The impact of Benjamin Bannaker on the ideology of Thomas Jefferson is arguably profound and its impact on the world through Jefferson are spectacular. I think Molly and her grandson Benjamin are amazing people.
Fact:
In her background she was convicted in a court for spilling milk, allegedly that of an obstinate cow, and for it she was sentenced to 7 years of indentured servitude. She was not hanged for theft because she was literate and thus was able to defend herself in court.
https://katedolan.com/molly-bannaky-the-amazing-woman-who-may-have-existed/
My problem with it:
Given basic human sustenance, that sounds like a very comparatively severe punishment for a relatively smaller crime.
Speculation on my part:
She was a young reproduction-age female servant, so it seems more anthropologically sound to imagine the sons of the owner wanted to have their way with her as opposed to shipping her to the other side of the world. It seems more plausible that either she was used as an example to cause other potential victims to comply, or that she was the preferred target and rejected with some brutality the advances of a highly-ranked suitor. The "Spilled milk" being reason for indure in a court suggests someone was willing to say it happened in a recordable way, perhaps the suitor or their parents. If the brutality were enough to anger them that would be reasonable. Several writings call the cow "obstinate" but given her life-story Molly is also obstinate (in several very commendable ways), and so the cow who kicked to cause the milk to spill could have been Molly herself. She could have kicked (and critically, in reproductive terms, wounded) someone trying to treat her like a cow.
Evidence:
I don't know much about 1600's literature, except that the King James bible came out in the early 1600's and likely used the language of the time.
In Genesis 38:9 it uses the verb spilling to refer to something criminal and worthy of death that was done to the male component of reproduction.
The culture did not change in the 1800's era as rapidly then as it does now, and the following seems to imply something similar.
There are a number of literature elements that discretely communicated horrible events, such as "The Yellow Wallpaper" from 1892 being a euphemised description of an assault from the victims perspective. The toadstools get violent meaning when considered to be reproductive organs. Impo the wallpaper is not insane at all, it is just sending a coded message describing a hideous set of experiences. It was not unknown to encrypt a hidden message using metaphor or symbolism.
Question:
I can't imagine the cost in prosecuting and lost value in losing a servant being worthwhile for literal spilled milk, although it was done by land-owners in 1690's England and thus is not my cultural values or economy, so is there any evidence that "Spilled Milk" is used as a euphemism for something relating to sexual assault or violent rejection of a "suitor"?
Places that I have looked:
This site (link) says the term came into documented usage in the mid 1600's the term was "shed". In that vernacular the shed is also applied to blood as a term for murder.
This link says it means " lament a disaster or a loss that can not be undone" but as an idiom, the actual disaster is not the literal spilling of literal milk.
Best Answer
The association of the phrase "spilled milk" with Benjamin Bannaker's grandmother occurred much later than the 1600s.
The first account of Bannaker's grandparents (Memoir of Benjamin Banneker 1845) says:
The second account is (Sketch of the Life of Benjamin Banneker 1854):
where "footnote 1" is:
So in the second account, she is no longer black but white, yet still no mention of milk.
Then in a third account (Banneker, The Afric-American Astronomer 1884) :
So finally in 1884 stealing milk is mentioned, but not the word "spilled", and stern laws for such an offense are specifically mentioned.
But to the general question of the consequence for stealing milk in England, the 1838 A Practical Guide to the Quarter Sessions, and Other Sessions of the Peace, Adapted to the Use of Young Magistrates, and Professional Gentleman at the Commencement of Their Practice, 4th edition at page 208 has boiler-plate language for indicting a person for stealing milk, and specifies the sentence: