Home Secretary Michael Howard's Green Paper on juvenile offending borrows Labour's clothes by identifying children at risk of offending (and their parents) and intervening early to stop them turning into criminals.
Labour, meanwhile, is more interested in crime than its causes and wants rid of doli incapax - the medieval doctrine that says 10 to 13-year-olds are incapable of evil intent - along with repeated cautions and a lack of secure accommodation.
Right-wing commentators joined left-wingers to complain about the possible departure of doli incapax, on the grounds that few children could be fully aware of the impact of their actions, and medieval lawmakers - not a notably liberal bunch - had rightly decided that this should be the responsibility of adults. In any case, the doctrine could be waived, as it was in the case against James Bulger's murderers.
Making the week in politics even odder was the further paradox that Michael Howard's genuinely new proposals were thoroughly upstaged by Jack Straw's repackaging of his Youth Crime scheme, officially launched last May.
It proves delinquent children - and their feckless parents - are an unashamedly populist hot electoral issue for both major parties. Teenagers in revolt and bad parents are ideal bogey figures, and it will be interesting to see what the victorious party actually does after May 1 - and whether it has any effect.
Paul Cavadino of the Penal Affairs Consortium is a lone voice expressing dismay. "The Green Paper is a peculiar mixture of constructive ideas to prevent delinquency and punitive parent-bashing measures which will do nothing to cut youth crime."
Regular stories of youngsters elevating two fingers to the criminal justice system and terrorising their communities were given an added twist last year by tales of delinquent pupils holding their schools to ransom, as at The Ridings.
Teaching unions - particularly the National Association of Schoolmasters Union of Women Teachers - have been among those shouting loudest about the need for firmer action. Nigel de Gruchy, the NASUWT general secretary, was trenchant in his approval. "It's a bloody good idea. I support Jack Straw's proposals in particular. Lowering the age of criminal responsibility is a perfectly good idea.
"Most of the kids we deal with are in trouble with the police before we refuse to teach them."
David Hart, general secretary of the National Association of Head Teachers, was enthusiastic but said more consultation was needed.
CRACKING DOWN ON CRIME:the main parties' proposals
* Local child crime teams made up of police, probation officers, teachers, social workers and health service representatives which would identify children at risk of offending; refer children and perhaps parents to schemes which might reduce the risk and maintain a register of programmes and services to help parenting, befriend children and help divert them from crime; * Parental Control Order, which could be used whether children had been convicted or were felt to be at risk of committing an offence and this was because of a lack of parental control. The Order might insist that children were taken to school every day, set a curfew or insist on attendance at an anti-crime scheme. Penalties for parents' non-compliance include a fine of up to Pounds 1, 000, a probation order, a curfew and electronic tagging or removal of driving licence.
Labour; * Parental Responsibility Order; * Community Safety Order - special injunctions against those who persistently make life hell for their neighbours; * swifter punishment - repeated cautions to be replaced with a final warning, which will be the signal for youth offender teams to intervene; * removal of doli incapax; * courts to decide on whether a young offender should be put into secure accommodation; * reform of youth courts to make them more inquisitorial, with parents as well as offender being confronted with the bad behaviour.