Ammi Ruhama Robbins Butler Jr. (September 4, 1821 – April 4, 1901) was an American lawyer, Democratic politician, and Wisconsin pioneer.

The case occurred when 23 year old seamstress Mary Ann Wheeler used a pistol to shoot John M. W. Lace in the back of the head while he was standing on a public sidewalk looking at a store window display, surrounded by witnesses.

Wheeler did not attempt to flee, and instead confessed when police arrived, subsequently revealing that she had bought the gun and a knife to kill Lace, having had a previous grievance with him, that she was happy she had done it, and that she would be content to be executed for it.

Her attorneys argued that her anguish from these circumstances, as well as a fear about public disclosure, led to a temporary insanity before the shooting.

[2][3] He was elected on the Democratic Party ticket, in 1865, to represent Milwaukee County in the Wisconsin State Assembly, but was not a candidate for re-election in 1866.

[1] His name was placed on several tickets as a Democratic candidate for Wisconsin Supreme Court in the 1869 election, but he did not seek the office and was not formally nominated.

[10] In the winter of 1888, Butler suffered a major fire at his estate in Oconomowoc, resulting in a loss of property valued between $30,000 and $40,000 (about $1M to $1.3M adjusted for inflation to 2024) as well as a number of items that were irreplaceable, including valuable paintings and his library.

Later in life, John Butler was prominent in the progressive push for a merit-based civil service in Wisconsin.