United Kingdom
A paper examining gender sentencing disparities in a large samples of assault, burglary and drugs offences found that male offenders are subjected to significantly harsher sentences, even when controlling for mitigating factors and case characteristics. Men were 2.84 times more likely than women to receive custodial sentence for the offence of assault, 1.89 more likely for the offence of burglary, and 2.72 more likely for offence related to drugs. For offences of assault, the gender factor was stronger than any other ‘harm and culpability’ factor with the exception of the ‘with intent to commit serious harm’ factor.[16]
France
A 2020 study shows that women receive 33% (15 days) shorter prison sentences than men, even when controlling for all observable characteristics – including a very precise description of the crime. When pairs of mixed-gender offender are convicted together the gender gap is even higher - men receive 38.7 additional prison days and 10.7 fewer suspended prison days.
From a procedural point of view, when controlling for the type of crime, men are on average judged after shorter investigations, and are more likely to be sentenced after an accelerated procedure. When taken to court, men are 20% less likely to be discharged (6% vs. 4%). In 2017, 19.9% of convicted men were sentenced to prison, compared to 8.5% of convicted women.[5]
United States
A 2001 University of Georgia study found substantial sentencing discrimination against men "after controlling for extensive criminological, demographic, and socioeconomic variables". The study found that in US federal courts, "males are... less likely to get no prison term when that option is available; less likely to receive downward departures [from the guidelines]; and more likely to receive upward adjustments and, conditioned on having a downward departure, receive smaller reductions than ... females".[6]
In 2006 Ann Martin Stacey and Cassia Spohn found that women receive more lenient sentences than men after controlling for presumptive sentence, family responsibilities, offender characteristics, and other legally relevant variables, based on examination of three US district courts.[7]
In 2012 Sonja B. Starr from University of Michigan Law School found that, controlling for the crime, "men receive 63% longer sentences on average than women do," and "[w]omen are…twice as likely to avoid incarceration if convicted", also based on data from US federal court cases.[8][9]
Variation among judges
In 2005 Max Schanzenbach found that "increasing the proportion of female judges in a district decreases the sex disparity" in sentencing which he interprets as "evidence of a paternalistic bias among male judges that favors female offenders".[4]
A 2020 study found with decreasing number of female judges in French courts the gender gaps in prison and probation sentences widens - prison and probation sentences are lighter for women, while suspended prison sentences are longer. The gender of the prosecutor seem to play no role.[5]
https://en.m.wikipedia.org/wiki/Sentencing_disparity