Picture this: you're 35, settled, reasonably together. You look back at the decisions your 19-year-old self made and feel a familiar wave of frustration. The credit card debt. The degree in a subject with no career path. The tattoo. Specifically the tattoo. What were you thinking?
Now imagine you could take that idiot to court.
The legal framework
For this to work, the law would need to treat your past self as a distinct legal entity. Not a different person exactly, but a version of you with separate liability. Think of it like suing a former business partner who happened to share your name, face, and bank account.
The cause of action would be negligence: your past self owed a duty of care to your future self, breached that duty through reckless or irresponsible behaviour, and caused quantifiable harm. Standard tort structure. The novel bit is that plaintiff and defendant are the same human being separated by time.
Courts would need a statute of limitations, obviously. You can't sue your 6-year-old self for eating too many sweets. Most proposals for this kind of framework (and yes, legal theorists have genuinely discussed temporal self-liability in academic journals) set the threshold at 16 or 18, when the law already considers you capable of adult decision-making.
What counts as actionable damage?
The floodgates question. If you can sue yourself for any bad decision, every human being alive has a case. So there'd need to be a threshold. Not just "I regret this" but "this caused measurable financial, physical, or psychological harm that a reasonable person at that age should have foreseen."
Dropping out of university to start a band that played three gigs and broke up? Probably actionable. The lost earning potential is quantifiable. A reasonable 19-year-old could foresee that "we'll definitely make it" is not a retirement plan.

Choosing the wrong A-levels? Harder. The causal chain between picking Geography over Economics at 16 and earning less at 40 has too many intervening variables. A good defence barrister (representing your past self, which we'll get to) would shred that argument.
Smoking through your twenties? Almost certainly actionable, given that health warnings have been mandatory on UK cigarette packets since 1971. Your past self knew. The evidence is literally printed on the product. Lung damage, reduced fitness, the cost of the cigarettes themselves: all quantifiable, all foreseeable.
Who defends you?
Here's where it gets properly strange. Your past self needs legal representation. They can't represent themselves because they don't exist any more, not as a present entity capable of attending court. So you'd need a court-appointed advocate arguing on behalf of a version of you that has been replaced by the version suing them.
The defence would almost always be the same: "My client was young, lacked information available to the plaintiff, and made decisions consistent with the norms of their peer group at the time." The "everyone was doing it" defence. It works surprisingly well for the twenties. Less well for the person who ignored their dentist for an entire decade.
And who pays the damages? You do. To yourself. The money moves from your bank account to... your bank account. Which makes the financial remedy essentially meaningless, unless the court structures it as a mandated savings plan or redirected spending. "The defendant's estate shall pay £15,000 into a pension fund for the plaintiff's benefit." You're paying your own pension with your own money, but now a judge told you to, so it actually happens.
The therapy industry explodes
Therapists have spent decades trying to get people to stop blaming their past selves and start accepting that personal growth means integrating who you were with who you are. This legal framework would undo all of that overnight.
Instead of "I've made peace with my twenties," you'd get "I'm in litigation with my twenties." The adversarial framing turns self-reflection into prosecution. Every regret becomes a potential claim. Every bad memory becomes evidence.

Therapists would need to pivot from helping people forgive themselves to helping people decide whether to file suit against themselves. The intake form at a counselling practice would have a checkbox: "Are you currently in legal proceedings with a previous version of yourself? If yes, please indicate which year(s) of yourself are named as defendant."
The court backlog
England and Wales already have a Crown Court backlog of roughly 73,000 cases. Add temporal self-liability to the mix and you'd see millions of new filings in the first year alone. Everyone has regrets. Most people have at least one decision they'd call genuinely negligent with the benefit of hindsight. The courts would collapse under the weight of retrospective grievance.
You'd need specialist tribunals. Temporal Liability Courts, probably, with judges trained in both tort law and developmental psychology. Expert witnesses would include actuaries (calculating lost earnings from stupid career moves), medical professionals (quantifying health damage from lifestyle choices), and possibly the plaintiff's mother, who warned them at the time and has been waiting decades to say "I told you so" under oath.
The real problem
The deeper issue with suing your past self isn't legal or practical. It's philosophical. It assumes that you at 20 and you at 40 are different enough to be adversaries, but similar enough to share responsibility. That your younger self owed you something, and failed to deliver.
But your younger self didn't know you. Couldn't have known you. They made decisions with the information, brain chemistry, and emotional maturity they had at the time. Holding them to the standards of a person who only exists because of those decisions is circular. You are the product of every stupid thing your past self did. Sue them out of existence and you might not end up as the person who wanted to sue them in the first place.
Besides, if the precedent exists, your future self can sue you too. And that version of you, the one looking back from 60, almost certainly thinks you're an idiot right now. Enjoy your coffee. The summons is coming.