How can AI help a law firm calculate limitation and key dates?

AI can help a firm work out limitation periods, deadlines and other key dates by counting from the dates in the papers and showing every step of the sum. Done well, it names the rule behind each step and points at the page where each date came from. It does not replace the firm's diary system or the judgement of the fee earner who is responsible for the date.

Why date calculation is a sensible task for AI

Missed and miscalculated dates are among the most common sources of complaints and claims against firms. The arithmetic itself is rarely hard, but it is easy to get wrong when you are busy: a start date read from the wrong document, a period counted in the wrong units, a weekend or a court holiday overlooked, or a rule applied that does not fit the matter.

This is work that suits an assistant. The task is bounded, the inputs are on the file, and the output can be checked. What matters is not speed but a result you can follow line by line and satisfy yourself is right.

What good looks like

A useful calculation should let you audit it without redoing it from scratch. Look for these features:

• A stated start date, with its source. The calculation should say which date it counted from and where in the papers that date appears.
• The working shown. Each step should be visible, not just the final answer. You should be able to see how the assistant got from the start date to the deadline.
• The rule for each step. Whatever period is being applied, the calculation should name the rule or provision that allows it, so you can go and read it yourself.
• A clear final date. Stated plainly, with any assumptions flagged.
• Honesty about gaps. If the papers do not contain a date the calculation needs, the assistant should say so rather than guess a plausible one.

A figure that arrives without any of this is worse than no figure at all, because it invites reliance you have not earned.

Where the responsibility stays

The firm's diary or case management system remains the record that governs. An AI calculation is a working, not an entry. The fee earner reads the working, decides whether it is right, and puts the date into the system that the firm actually relies on. Nobody should be diarising straight from a chat window.

Two points deserve particular care.

First, the assistant works from the dates it can find in the papers. If the papers are incomplete, or if a date on the file is itself wrong, the calculation will be built on that. You are checking the inputs as much as the sum.

Second, some periods turn on facts and judgement that no document states cleanly: when a cause of action accrued, when a client's knowledge began, whether a period was extended by agreement or by an order. An assistant can lay out the possibilities and show the arithmetic for each, but the choice between them is legal judgement, and that is yours.

How to use it in practice

A workable routine looks like this:

1. Ask for the calculation and require the working, the source of each date, and the rule behind each step.
2. Check the start date against the document it came from.
3. Read the rule the assistant applied and confirm it is the right one for this matter.
4. Satisfy yourself the counting is correct, including any weekends, bank holidays or court office rules that apply.
5. Enter the confirmed date in the firm's diary, and diary a reminder well before it.

For limitation in particular, treat the assistant's output as a prompt to think, not a conclusion. The Limitation Act and the rules around it contain plenty that depends on facts you may not have yet. Where those facts are unsettled, note the calculation as provisional and revisit it when they firm up.

Coverage and its limits

Be aware that official sources are better covered for some jurisdictions than others. For matters governed by the law of Scotland or Northern Ireland, coverage of the relevant sources can be thinner, and a careful assistant should tell you so in the answer rather than present a confident figure it cannot fully support. Treat any such answer as a starting point for your own checking against the correct rules for that jurisdiction.

Where Alesis fits

Alesis counts key dates and figures with the working shown, each step carrying the rule that allows it, and it says plainly that the firm's diary system still governs. It reads the papers page by page and names the page each date came from, and it reads legislation and official guidance at the source so you can open them in one click. Where coverage of official sources is thinner, in Scotland and Northern Ireland, it says so in the answer. Alesis assists qualified professionals and does not replace them, and it does not provide legal advice.