More than half of all criminals ordered to wear an electronic tag break the terms of their curfew, a review has found.
Some 59% of offenders ordered to be tagged by courts receive at least a warning, while more than a third are sent back to court following more serious violations, an analysis of more than 80 cases by Her Majesty's Inspectorate of Probation (HMIP) found.
But Chief Inspector Liz Calderbank said the most concerning finding was that in a fifth of cases where there were violations, inspectors could not even see who was supposed to be in charge.
Justice Secretary Kenneth Clarke set out proposals to extend the use of tagging in plans to radically overhaul community sentences in March.
Their use by courts has already more than doubled in the last six years, with a total of 80,000 offenders being tagged in 2010/11.
This included 65,000 by courts and 15,000 who were released early from prison, which cost around £100 million, about a tenth of the total probation budget.
However tagging offenders is much cheaper than the £45,000 annual cost of a prison place.
Use of the tags was up from a total of 51,000 in 2005/6, including 31,000 by courts and 20,000 post-release, figures in the report showed.
But the inspectors found court paperwork was unclear, illegible or wrong, leading to delays in enforcement or action having to be stopped once it emerged that the person who thought they were responsible had no legal authority.
The identify of the offender manager responsible for taking any action could not be established from the paperwork because it was often unclear whether it was only a single requirement, for which the tagging firms were responsible, or one with multiple requirements, which would mean the probation service were responsible.
It also emerged that offenders could break the terms of their curfew for up to two hours before even receiving a warning, and for a total of four hours over numerous occasions before court action was considered.
And breaking the curfew for 11 hours and 59 minutes of a 12-hour order would still only count as a less serious violation, the report said.
Ms Calderbank also warned that it was "deeply worrying" that the review found one case where a violent offender who had beaten his wife was sent back to their home address, despite the woman initially saying that she did not want him there.
He was later charged with common assault on his partner during the eight-week curfew period.
Ms Calderbank said these issues should be picked up in pre-sentence reports and assessments, but just 29% of the cases reviewed involved such a report, significantly down from 90% of cases in the last review in 2008.
In 2008, 28% of these cases included a home visit, but there was no evidence of any home visits in the latest review.
Home visits had also "virtually disappeared" for prisoners being released early under the home detention curfew scheme, being replaced by a simple telephone call, an analysis of a further 40 cases showed.
Prisoners could just arrange for their friend to be at home and agree for the offender to be released, Ms Calderbank said.
Asked if tagging was simply a cheap way to control people, Ms Calderbank said tagging should not be used indiscriminately, adding: "If you're not actually managing their behaviour, it doesn't matter what the cost of it is, it's not cheap."
She went on: "We think that electronically-monitored curfews can play a very useful role in managing people who offend in the community, whether they've come from prison or the courts.
"But we do think it needs to be looked at. We think they've got a lot of potential, but we don't think that potential is being realised.
"Unless curfews are located as part of an overall way of working with offenders, that's not going to happen."
Justice Minister Crispin Blunt said: "New contracts for the provision of electronic monitoring services come into effect in April 2013.
"This will provide an opportunity to implement necessary changes, explore new technology and ensure it is used as effectively as possible.
"The call for a smarter, more integrated approach is very much in line with the government's initiatives in reducing re-offending and protecting the public.
"Properly administered new generation 'tagging' can impose a punishment, promote improved behaviour and give victims reassurance.
"This report helps illustrate the potential as well as providing lessons on how to improve current administration."
Andrew Neilson, director of campaigns at the Howard League for Penal Reform, said: "The danger is that the tagging is used as a one-size-fits-all approach.
"We are concerned at the danger of over-relying on technology at the expense of tailored support with staff contact and interventions that help people to change their lives."