After her trial, she studied law and became the first female lawyer admitted to the bar in the Washington Territory and in the state of Oregon.

[1] Her parents, Johannes Gysin and Elisabeth Grieder, were Swiss immigrants to France and worked in a silk mill.

[2] Some stories say she moved in order to provide income for her poor family, others recount that she was attempting to make it on her own.

[3] Daniel Leonard owned a hotel and ferry in the Columbia River Gorge along the Oregon Trail.

[1][2] In the Fall of 1877, Daniel filed for divorce, claiming Mary was having an affair with one of the boarders at the hotel, Nathaniel Lindsay.

[1] Daniel said Mary was the abuser, denied him sexual relations, that she stole money and the deeds to his property, and the affair with Lindsay among other charges.

[3] In late December Mary wrote a scathing letter to Daniel warning him to follow the court's instructions to provide maintenance and threatened to get even with him.

[3] While the trial was pending, women's right activist Abigail Scott Duniway used her newspaper, The New Northwest, to support Mary's defense.

[3] At the time, many believed that she was in fact guilty of killing Daniel, but as he was disliked, people felt sympathy for her.

[1][3] Later that year Mary collected Daniel's estate as the sole heir and moved to Portland where she went into business as the owner of boardinghouses.

[1] Mary Leonard then developed a law practice in Portland with a reputation for poor writing but good courtroom skills.

[3] After a trial described as a circus, she was acquitted of the charges,[3] but did admit on the witness stand that she carried a small gun and a hammer.

[3] She was released after a short time on a writ of habeas corpus drawn up by other attorneys, as the minimum fine for the charge was $25.