A lawyer I admire asked me to talk to her colleague about expert reports.  I haven’t had that conversation yet, but the request got me thinking about the elements of a competent expert report, especially reports in my areas of computer forensics and digital evidence.  I dashed off ten things I thought contribute to the quality of the best expert reports.  If these were rules, I’d have to concede I’ve learned their value by breaking a few of them.  I’ve left out basic writing tips like “use conversational language and simple declarative sentences.” There are lists of rules for good writing elsewhere and you should seek them out.  Instead, here’s my impromptu list of ten tips for crafting better expert reports on technical issues in electronic discovery and computer forensics:

1. Answer the questions you were engaged to resolve.
2. Don’t overreach your expertise.
3. Define jargon, and share supporting data in useful, accessible ways.
4. Distinguish factual findings from opinions.
5. Include language addressing the applicable evidentiary standard.
6. Eschew advocacy; let your expertise advocate for you.
7. Challenge yourself and be fair.
8. Proofread.  Edit.  Proofread again. Sleep on it. Edit again.
9. Avoid assuming the fact finder’s role in terms of ultimate issues.
10. Listen to your inner voice.

Most of these are self-explanatory but please permit me a few clarifying comments.

Answer the questions you were engaged to resolve.

My pet peeve with expert reports is that they don’t always address the questions important to the court and counsel.  I’ve seen reports spew hundreds of pages of tables and screenshots without conveying what any of it means to the issues in the case.  Sometimes you can’t answer the questions.  Fine.  Say so.  Other times you must break down or reframe the questions to conform to the evidence.  That’s okay, too, IF it’s not an abdication of the task you were brought in to accomplish.  But, the best, most useful and intelligible expert reports pose and answer specific questions.

Don’t overreach your expertise.

The standard to qualify as an expert witness is undemanding: do you possess specialized knowledge that would assist the trier of fact in understanding the evidence or resolving issues of fact? See, e.g., Federal Rule of Evidence 702.  With the bar so low, it can be tempting to overreach your expertise, particularly when pushed by a client to opine on something you aren’t fully qualified to address.  For example, I’m a certified computer forensic examiner and I studied accounting in college, but I’m not a forensic accountant.  I know a lot about digital forgery, but I’m not a trained questioned document examiner.  These are specialties.  I try to stay in my own lane and commend it to other experts.

Define jargon, and share supporting data in useful, accessible ways.

Can someone with an eighth-grade education and no technical expertise beyond that of the average computer user understand your report?  If not, you’re writing for the wrong audience.  We should write to express, not impress.  I love two-dollar words and the bon mot phrase, but they don’t serve me well when writing reports.  Never assume that a technical term will be universally understood.  If your grandparents wouldn’t know what it means, define it.

Computer forensic tools are prone to generate lengthy “reports” rife with incomprehensible data.  It’s tempting to tack them on as appendices to add heft and underscore how smart one must be to understand it all.  But it’s the expert’s responsibility to act as a guide to the data and ensure its import is clear.  I rarely testify—even by affidavit–without developing annotated demonstrative examples of the supporting data.  Don’t wait for the deposition or hearing to use demonstrative evidence; make points clear in the report.

Too, I’m fond of executive summaries; that is, an up-front, cut-to-the-chase paragraph relating the upshot of the report.

Distinguish factual findings from opinions.

The key distinction between expert and fact witnesses is that expert witnesses are permitted to express opinions that go beyond their personal observation.  A lay witness to a crash may testify to speeds based only upon what they saw with their own eyes.  An accident reconstructionist can express an opinion of how fast the cars were going based upon evidence that customarily informs expert opinions like skid marks and vehicle deformation.  Each type of testimony must satisfy different standards of proof in court; so, to make a clear and defensible record, it’s good practice to distinguish factual findings (“things you saw”) from opinions (“things you’ve concluded based upon what you saw AND your specialized knowledge, training and experience”).  This  naturally begets the next tip:

Include language addressing the applicable evidentiary standard.

Modern jurisprudence deploys safeguards like the Daubert standard to combat so-called “junk science.”  Technical expert opinions must be based upon a sound scientific methodology, viz., sufficient facts or data and the product of reliable principles and methods.  While a court acting as gatekeeper can infer the necessary underpinnings from an expert’s report and C.V., expressly stating that opinions are based upon proper and accepted standards makes for a better record.

Eschew advocacy; let your expertise advocate for you.

Mea culpa here.  Because I was a trial lawyer for three+ decades, I labor to restrain myself in my reporting to ensure that I’m not intruding into the lawyer’s realm of advocacy.  I don’t always succeed.  Even if you’re working for a side, be as scrupulously neutral as possible in your reporting.  Strive to act and sound like you don’t care who prevails even if you’re rooting for the home team.  If you do your job well, the facts will advocate the right outcome.

Challenge yourself and be fair.

My worst nightmare as an expert witness is that I will mistakenly opine that someone committed a bad act when they didn’t.  So, I’m always trying to punch holes in my own theories and asking myself, “how would I approach this if I were working for the other side?”  Nowhere is this more important than when working as a court-appointed neutral expert.  Even if you’d enjoying seeing a terrible person fry, be fair.  You stand in the shoes of the Court.

Proofread.  Edit.  Proofread again. Sleep on it. Edit again.

Who has that kind of time, right?  Still, try to find the time.  Few things undermine the credibility of an expert report like a bunch of spelling and grammatical errors.  Stress and fatigue make for poor first drafts.  It often takes a good night’s sleep (or at least a few hours away from the work) to catch the inartful phrase, typo or other careless error.

Avoid assuming the fact finder’s role in terms of ultimate issues.

Serving as a court Special Master a few years back, I opined that the evidence of a certain act was so overwhelming that the Court should only reach one result.  Accordingly, I ceased investigating the loss of certain data that I regarded as out-of-scope.  I was right…but I was also wrong.  The Court has a job to do and, by my eliding over an issue the Court was obliged to address, the Court had to rule without benefit of what a further inquiry into the missing evidence would have revealed. The outcome was the same, but by assuming the factfinder’s role on an ultimate issue, I made the Court’s job harder.  Don’t do that.

Listen to your inner voice.

In expressing expert opinions, too much certainty—a/k/a arrogance–is as perilous as too much doubt.  Perfect is not the standard, but you should be reasonably confident of  your opinion based on a careful and competent review of the evidence.  If something “feels” off, it may be your inner voice telling you to look again.