Joint Retainer Agreements in Family Law: The Good, the Bad, and When They Actually Make Sense

In family law, there are two ways to bring an expert into a file. Each side can hire their own — the traditional adversarial approach — or both sides can agree to share one expert under a Joint Retainer Agreement. Also known as a "joint retainer," a "jointly retained expert," or, in the friendlier corners of the profession, "the reasonable option."

Joint retainers have become increasingly common in Ontario family law, particularly for business valuations, income determinations for support purposes, and other situations where specialized financial expertise is needed. Courts encourage them. Lawyers often suggest them. And in the right circumstances, they can save everyone involved a significant amount of time and money.

But they're not right for every file. Let's get into why.

What a Joint Retainer Agreement Actually Is

A Joint Retainer Agreement is a written agreement between both spouses (and usually their lawyers) to engage a single expert to provide a report on a specific issue. The expert is retained by both sides simultaneously, paid by both sides (usually split equally, though other arrangements are possible), and produces one report that both sides receive at the same time.

Crucially, the jointly retained expert is not advocating for either side. Their job is to provide an independent, professional opinion based on the documents and the relevant professional standards. They work for both parties and owe duties to both parties.

Contrast this with the traditional adversarial model, where each side hires their own expert, each expert produces their own report, and the two experts often arrive at meaningfully different conclusions. The judge then has to decide which expert to believe, which leads to cross-examinations, rebuttal reports, and a trial that can take days.

A joint retainer short-circuits all of that. One expert. One report. One number.

The Good: Why Joint Retainers Often Make Sense

They're cheaper. Significantly cheaper.

When each side hires their own valuator, you're paying for two full engagements. Two document reviews. Two normalization exercises. Two sets of professional fees. Then you often end up paying legal fees on top to deal with the discrepancies between the two reports. A joint retainer cuts the expert costs roughly in half, and usually reduces the downstream legal fees as well because there's less to fight about.

They reduce conflict and speed things up.

Litigation is exhausting. Every additional report, every additional cross-examination, every additional back-and-forth between experts adds weeks or months to the process. A joint retainer gets to a conclusion faster because there's no competing report to respond to. The expert does the work, delivers the report, and both sides are working from the same foundation.

They produce results that are harder to challenge.

When both sides agree on the expert upfront, neither side can credibly attack the expert's methodology or independence later. The expert was chosen by both parties. The expert was paid by both parties. The expert followed the process that both parties agreed to. The resulting report carries significant weight with the court and is rarely overturned on appeal.

Judges like them.

Ontario courts have become increasingly supportive of joint expert engagements, particularly in family law. Some judges actively encourage joint retainers during case conferences. Some family law Rules (and practice directions) specifically contemplate joint experts. A file with a jointly retained expert tends to be viewed favourably by the court because it signals that both parties are engaging with the process in good faith.

They work best when the issue is technical, not strategic.

Business valuations, income determinations under the Federal Child Support Guidelines, and imputing income for support purposes are all areas where the analysis is driven by professional standards rather than advocacy. A competent valuator applying accepted methodology should arrive at a similar range regardless of who hired them. In those situations, paying two experts to do essentially the same analysis is often wasteful.

The Bad: When Joint Retainers Go Wrong

Joint retainers aren't a magic solution. There are real downsides, and cases where they absolutely do not work.

You lose control over the process.

When you hire your own expert, you can direct the scope of work, request specific analyses, and have direct communication with the expert throughout the engagement. With a joint retainer, the scope is negotiated between both sides (and often their lawyers), and communications with the expert are typically copied to the other side. This is by design, because the expert has to remain independent. But it means you can't just pick up the phone and ask the valuator to look at something specific without the other side being aware.

The report might not go your way.

This is the part that catches some people off guard. A jointly retained expert is not on your team. They're not advocating for your position. They're not going to find creative ways to interpret the evidence in your favour. They're going to apply professional standards to the documents and produce a number. Sometimes that number will be higher than you wanted. Sometimes it will be lower than your spouse wanted. And because you both agreed to the process, neither side has much room to complain afterward.

Disputes over scope can derail the engagement.

Before the expert starts, the parties have to agree on the scope of work. What's being valued? As of what date? Using what assumptions? What documents will be provided? If the two sides can't agree on the scope, the joint retainer stalls before it even begins. This is more common than you'd think, particularly in high-conflict files where the parties disagree about basic facts.

It requires a minimum level of cooperation.

A joint retainer only works if both sides are willing to engage constructively. If one side is uncooperative, withholds documents, or tries to influence the expert inappropriately, the process breaks down. In those situations, you're better off with separate experts from the start.

The expert's scope might be too narrow.

In some files, you genuinely do need a report that advocates for a specific position, or a report that addresses issues beyond what the other side is willing to include in the joint retainer. If the scope is limited to "what's the value of the business on the date of separation," but you also need analysis of historical cash flows, disguised compensation, or comparative industry data, those may not make it into the joint report. You might end up needing a second expert anyway.

It can feel uncomfortable.

For many business owners going through a divorce, the idea of sharing an expert with their spouse feels wrong. You're used to hiring professionals who work for you. Your lawyer works for you. Your accountant works for you. Your tax advisor works for you. Hiring an expert whose loyalty is split can feel counterintuitive, even when it's the most practical option.

When a Joint Retainer Is the Right Call

Joint retainers tend to work well in files with the following characteristics:

• Both parties are reasonably cooperative and willing to engage with the process in good faith
• The issue is primarily technical — such as a business valuation or income determination — rather than factual (i.e., neither side is alleging fraud, hidden assets, or gross manipulation of the financials)
• The financial records are reasonably organized and both sides agree on what documents will be provided
• Cost is a meaningful consideration (which it almost always is)
• Both lawyers are supportive of the joint retainer approach and can agree on scope
• Neither side is planning to litigate aggressively on the expert evidence itself

When a Joint Retainer Is the Wrong Call

Joint retainers are usually a poor fit when:

• There are allegations of hidden income, undisclosed assets, or financial misconduct. In those cases, you need an expert who can investigate, follow trails, and advocate for findings. That's not what a joint expert does.
• The parties fundamentally disagree about the facts. If one side says the business is worth $500,000 and the other says it's worth $3 million because they believe the books are manipulated, a joint retainer won't resolve that. Each side needs their own expert.
• One party is uncooperative or obstructive. Joint retainers require both sides to play by the same rules. If one side is going to stonewall on disclosure or try to manipulate the process, the joint retainer becomes a tool for delay.
• The scope of work is contested. If the two sides can't agree on what the expert should actually analyze, you're better off each retaining your own expert with your own scope.
• There are unusual complexities. Multiple businesses, cross-border assets, trust structures, complex share arrangements, or other unusual features may require specialized analysis that doesn't fit neatly into a joint engagement.

How Clarity CPA Helps

Clarity CPA provides forensic accounting and valuation services in Ontario family law matters, including as a jointly retained expert.

When engaged on a joint retainer, our role is clear:

• Independent analysis. We apply professional standards, not advocacy. Both parties receive the same information, the same access, and the same report at the same time.
• Clear scope from the outset. We work with both sides (and their lawyers) to agree on the scope of work before the engagement begins, so there are no surprises about what the report will or won't cover.
• Transparent communication. All substantive communications are copied to both parties or their counsel. No side conversations. No preferential treatment.
• Professional reporting. Our reports are prepared to the standards expected in Ontario family law matters, with reasoning that can withstand scrutiny if the report is ever challenged or relied upon in court.
• Cost-conscious engagement. We scope the work efficiently and communicate about fees transparently, because we understand that in most family law files, cost is a real concern for both parties.

We also regularly act as a single-party expert where the circumstances call for it, including in files involving allegations of financial misconduct, income manipulation, or undisclosed assets. Not every file is suited to a joint retainer, and we help clients and their lawyers assess which approach makes the most sense based on the specific facts.

The Bottom Line

Joint Retainer Agreements are a good option in the right circumstances. They save money, reduce conflict, and produce reports that both sides can rely on. They're not a universal solution, and they require both parties to engage constructively. But when the file is suitable for a joint expert, choosing that path can meaningfully reduce the stress, cost, and duration of the family law process.

The decision about whether to proceed with a joint retainer should be made in consultation with your family law lawyer, based on the specific facts of your file. If you're not sure whether a joint retainer makes sense for your situation, it's worth having a conversation with both your lawyer and a qualified expert before committing one way or the other.

Clarity CPA provides forensic accounting and business valuation services for family law matters in Ontario, including jointly retained and single-party engagements. For inquiries about retaining Clarity CPA on a family law file, contact us to discuss scope, timing, and fees.