Browser Compatibility Notification
It appears you are trying to access this site using an outdated browser. As a result, parts of the site may not function properly for you. We recommend updating your browser to its most recent version at your earliest convenience.

Emergency? Call 9-1-1

Non-Emergency? Call 1 (866) 876-5423

Decrease Text Size Default Text Size Increase Text Size |
Print Link


Posted on Thursday February 08, 2018



York Regional Police have charged a 28-year-old Vaughan woman in connection with a sexual assault investigation involving a teenaged male student.

On January 26, 2018, police began an investigation after receiving information about a teacher believed to be involved in a sexual relationship with a teenaged student between October and December 2017.

The accused has been working as an occasional high school supply teacher with the York Catholic District School Board since 2014. Investigators want to ensure that there are no additional victims and are asking anyone with information to please come forward.


  • Marianna  RIOSSI, 28, of the City of Vaughan



Sexual Assault x3

Sexual Exploitation x3

The accused will be appearing before the Ontario Court of Justice in Newmarket on March 6, 2018.

A sexual assault includes any non-consensual contact of a sexual nature. York Regional Police encourages victims to report incidents of sexual assault, including historical offences.  There is no statute of limitations for sexual offences and offenders can be prosecuted well after the date of the offence. If someone is not ready to report, however is seeking support, please contact York Region Victim Services , the Cedar Centre or the Women’s Support Network or. Additional resources and information can also be found on our website

Anyone with information is asked to contact the York Regional Police Special Victims Unit at 1-866-876-5423, ext. 7075, or contact Crime Stoppers at 1-800-222-TIPS, leave an anonymous tip online at,