'Urgent need for stalking law'
The prison sentences being handed down to stalkers are so short that rehabilitation and treatment is impossible, campaigners have said.
Some 20 stalkers a year are jailed for longer than 12 months for putting a victim in fear of violence, the probation union Napo said.
Some were behind bars for just days, while others were sentenced to community orders and "inappropriate" domestic violence courses, it said.
Calling for the law to be changed to tackle the problem of stalking earlier, Napo said tens of thousands of victims were being let down by the criminal justice system.
Shadow home secretary Yvette Cooper has committed Labour to the move, blaming a "lack of clarity" in the law for allowing stalking cases to escalate into still more "heinous" crimes against both women and men.
Some 120,000 victims, mostly women, are stalked each year, but just 53,000 are recorded as crimes by police and only one in 50 of these lead to an offender being jailed, Napo said.
Harry Fletcher, the union's assistant general secretary, said: "It is abundantly clear that if the criminal justice system does not intervene early to prevent stalking behaviour, then that behaviour escalated to violence and even murder. There is virtually no training for any criminal justice professional in understanding stalking and therefore it is no surprise that the response is so inadequate."
He continued: "There is an urgent need for a stalking law and for the offence of harassment to be tried not just in the magistrates' but in the crown courts. If professionals were trained and intervened early this would save lives, save money and save victim misery."
In 2009/10, one in 50 of those charged under the Protection from Harassment Act 1997 received a custodial sentence, with an annual average of 20 offenders being jailed for more than a year for putting someone in fear of violence, a report by Napo showed.
Prime Minister David Cameron has said the Government would look at creating a new offence of stalking. Last month, the Home Office announced a three-month consultation on the problem of stalking after victims complained of feeling "let down" by the justice system.