Victorian police say they need new powers to charge family violence and sexual offenders who strangle their victims.

The risk of women being murdered dramatically increases - one study found the odds leapt by 800 per cent - if their partner or former partner attempts to strangle them.

This week, an inquest into the 2011 death of Mornington Peninsula woman Joy Rowley revealed the 60-year-old was choked unconscious eight months before she was strangled to death.

Joy Rowley was murdered in 2011.

The head of Victoria Police’s response to family violence told the Coroners Court that attempted strangulation was a significant contributing factor to Ms Rowley’s risk and vulnerability and it should be a stand-alone offence.