Womens hands behind prison bars Getty Images

You’re probably familiar with America’s most notorious Irish criminals.

From the "Irish Mob" which terrorized major U.S. cities in the 19th century to the "Winter Hill Gang" and Whitey Bulger out of Boston, much ink has been spilled on Irish American crime.

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But seldom do you hear of female Irish American criminals.

Lizzie Halliday was described by the New York Times at her death in 1918 as the “worst woman on earth." Image: WikiCommons

In fact, there was once a time when Irish women were the largest ethnic group in  North American courts and prisons.

But now, after three years of research, the “Bad Bridget” project, has been able to shed light on some of Americas less than glamorous Irish immigration stories.

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Dr. Elaine Farrell and Dr. Leanne McCormick led a team to investigate the criminal and deviant Irish women in North America from 1838-1918 and found that between 1860 and 1881, Irish women in Toronto Jail made up around 60 per cent of the entire female prison population.

In fact, they outnumbered every other nationality - including Canadian-born women - combined.

Irish women also occasionally outnumbered Irish men.

In 1861, Irish women were arrested 12,603 times in New York, while 11,672 arrests involved Irish men.

One of the most dangerous amongst them was County Antrim woman Lizzie Halliday - the first woman sentenced to execution in the US by electric chair.

Described by the New York Times at her death in 1918 as the “worst woman on earth," Halliday had been married six times by the age of 30 and her involvement in her husbands’ deaths was unquestioned.

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That was until the body of her sixth husband was discovered under the floorboards of their house along with two neighbors found dead in a nearby barn.

Her perceived mental ill-health saved her from electrocution and instead, Halliday was incarcerated in an asylum, where she would go on to kill an attendant by stabbing her with shears.

During this period, more than five and a half million migrants departed Ireland for North America. 

Women tend to be fewer in crime statistics generally, both historically and today, so the overrepresentation of Irish women,  according to the authors, is particularly striking.

"Stories of Irish criminal women also make clear their poverty, the hardships experienced as a result of deficits in education or employability skills, their difficulties adjusting to new cultures and climates, their lack of support networks abroad, and the discrimination and prejudice that they faced, often cast as brutish, ignorant, diseased or uncivilized," they told the Irish Times.

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How do you feel about this latest research on Irish American women? Let us know in the comments below.