Can AI help us check the other side's bill of costs?

Yes, for the parts of the job that are arithmetic and cross-referencing. An AI assistant can read a served bill alongside the papers you hold, pull out what is claimed for each phase or period, flag entries that do not match anything on your file, and total the figures with the working shown. What it cannot do is decide what is reasonable or proportionate, or settle how hard to push a point; that is a judgement for a costs lawyer or a fee earner who knows the case.

What a bill check actually involves

Strip out the advocacy and the work is largely comparison. You are asking a short list of questions, over and over, across hundreds of lines:

• Does the work claimed correspond to something that happened on the matter as you understood it?
• Are the same steps claimed twice, or under two different descriptions?
• Do the hours attributed to a fee earner square with the documents that exist?
• Are rates and grades consistent across the bill, and consistent with anything previously approved or agreed?
• Where there was a budget, does the bill sit against it in a way you can follow?
• Do the stated totals add up, and do the schedules reconcile to the summary?

None of that requires an opinion. It requires patience and an accurate memory of a long file. That is exactly the kind of task where an AI assistant earns its place, and exactly the kind where a tired fee earner at seven in the evening does not.

A sequence that works

1. Put the bill and the relevant file papers into one place for the matter: your correspondence, attendance notes, court documents, any budget and any previous costs correspondence.
2. Ask for a structured read of the bill first: what is claimed, by whom, at what rates, in what periods or phases, with the totals as stated.
3. Ask it to check the arithmetic and tell you where the schedules and summary disagree.
4. Ask for entries that have no visible counterpart in your papers, with the dates and descriptions set out, so you can look at each one yourself.
5. Ask for apparent duplication: two entries for what looks like the same step, or work claimed by two fee earners on the same event.
6. Ask for the periods where activity claimed is heaviest, and compare that against what you know was happening on the case at the time.
7. Take the output to the person who will settle the points of dispute, and have them decide what is worth running.

Step seven is not a formality. A long list of queries is not the same as a good set of points of dispute. Somebody has to decide which points matter, which are worth the assessment time, and which are better left alone.

What it cannot decide for you

An AI assistant can tell you that four hours were claimed for drafting a document. It cannot tell you whether four hours was reasonable for that document in that case. Reasonableness and proportionality are judgements shaped by the issues, the conduct of both sides and the value at stake, and the Civil Procedure Rules leave them to be assessed, not computed.

It also cannot know what it has not been shown. If your file is incomplete, if attendance notes were never made, or if work genuinely happened that left no paper trail on your side, the absence of a counterpart in your papers proves nothing on its own. Treat every flagged entry as a question to answer, not a point to take.

And it cannot tell you what the other side will accept. That comes from experience of assessment and of the opponent.

Risks to watch

Confidence in the wrong direction. A tool that produces a tidy list of objections can make a weak challenge look strong. Read the underlying entries yourself before anything goes out under your name.

Scanned bills. Many bills arrive as scans or as exports that lose their structure. If a page cannot be read properly, you need to know that rather than have it quietly dropped from the analysis.

Your own file. Checking someone else's bill often exposes gaps in your own record keeping. That is uncomfortable but useful, and it is worth capturing the lesson for the next matter.

Figures without working. A total you cannot trace back to its components is no use at an assessment. Insist on seeing how any number was reached, and check the parts you intend to rely on.

Confidentiality. A served bill contains detail about the other side's conduct of the case, and your own file contains privileged material. Whatever tool you use needs to handle both on terms your firm has actually read.

Where Alesis fits

Alesis answers questions about a matter from the matter's own papers and names the page each answer came from, so an entry you want to challenge can be traced back to what your file does or does not show; where the papers do not say, it says so. It counts figures with the working shown, each step carrying the rule that allows it, and documents are read page by page, so any page it could not read is flagged rather than skipped. It prepares drafts for a qualified person to review and sign off, and it assists qualified professionals rather than replacing them.