The reference call lasted eight minutes. The former manager said the candidate was "great" and "would definitely recommend" them. We hired, and within three months we were managing the person out for performance issues that—we later learned—were well-known at their previous company.
The reference check had failed because we asked the wrong questions. We got the answers references are trained to give, not the answers that would have revealed the truth.
After analyzing reference checks for over 300 engineering hires at SmithSpektrum, I've learned that effective reference checking is a skill. The questions you ask, how you ask them, and how you interpret the answers determine whether you learn something useful or just complete a ritual[^1].
Why Reference Checks Fail
Most reference checks surface little real information for predictable reasons.
References are coached. Candidates choose their references carefully and often prep them on what to say. You're hearing a curated version of reality.
References fear liability. Many companies have policies against providing substantive references. Former managers may only confirm dates and titles.
Questions invite clichés. "What are their strengths?" invites "They're a great team player." You've learned nothing.
Nobody listens for nuance. The hesitation before an answer, the carefully chosen words, the topics avoided—these matter as much as what's said.
Structuring the Reference Check
A 20-25 minute call can surface substantial signal if structured well.
| Phase | Time | Purpose |
|---|---|---|
| Context setting | 3 min | Establish relationship, role context |
| Performance | 8 min | Specific accomplishments and impact |
| Working style | 5 min | How they collaborate, communicate |
| Development areas | 5 min | Growth edges, areas to support |
| Final questions | 4 min | Direct hire/not hire signal |
The Opening
Start by establishing context:
"Thanks for taking the time. To give context, [Candidate] is being considered for [specific role]. I have a few questions about your time working together. I'd appreciate candid feedback—it helps us set them up for success if they join."
Framing around "setting them up for success" signals you want real information, not just validation.
Then confirm the relationship:
"Can you describe how you worked with [Candidate]? What was your role and what was theirs?"
This establishes whether this is a direct manager (strongest signal), peer (useful signal), or indirect relationship (weaker signal).
Questions That Work
Performance Questions
"Can you tell me about a specific project they led or contributed to significantly?"
Listen for: concrete details, measurable outcomes, their specific contribution versus team work. Vague answers suggest either poor memory or lack of significant contribution.
"How did their performance compare to others at the same level?"
This forces relative comparison. "Good" is meaningless; "top 10% of engineers I've managed" is specific. If they hesitate or deflect, that's informative.
"What did they accomplish that wouldn't have happened without them?"
This identifies unique contribution. If the answer is vague or they can't think of anything, the candidate may be a solid contributor but not a differentiator.
Technical Questions
"How would you describe their technical judgment?"
Listen for: examples of good decisions, instances where they identified problems others missed, or alternatively, hedged answers that suggest gaps.
"What's the most complex technical problem you saw them solve?"
Specific, detailed answers indicate strong technical capability. "They were good technically" without specifics suggests limited depth or limited visibility.
"How did they handle situations where they didn't know the answer?"
This reveals learning orientation and intellectual honesty. Look for: comfort admitting gaps, proactive learning, asking for help appropriately.
Collaboration Questions
"How did they work with people who disagreed with them?"
This surfaces conflict style. Red flags: "they could be difficult," long pauses, "they had strong opinions." Green flags: "they listened well," "they found common ground."
"How did more junior team members experience working with them?"
This reveals whether they lift others up or bulldoze. If the reference can't answer or deflects, that may indicate the candidate didn't invest in others.
"What was it like to work with them on a tight deadline or in a stressful situation?"
Stress reveals character. Listen for: how they handled pressure, whether they supported teammates or created additional stress, whether they stayed focused.
Development Questions
"What would make them even more effective in their next role?"
This reframes "weaknesses" as development areas, making references more comfortable sharing. Listen carefully—this is where real growth edges emerge.
"What kind of manager or environment helps them do their best work?"
This reveals what support they need. It's not negative information—it's practical guidance for their success if you hire them.
"If you were their manager again, what would you work on with them?"
This makes it personal and specific. If a former manager would work on nothing, that's either a unicorn or a deflected answer.
The Closing Questions
"Would you hire them again? Would you want to work with them again?"
This is the most direct signal. Listen to tone as much as words. Enthusiastic "absolutely" differs dramatically from "yes, probably" or hesitation.
"Is there anything I haven't asked that would be important for us to know?"
This opens space for information they want to share but weren't asked about. Sometimes the most important signal comes here.
"If we hire them, what advice would you give me as their manager?"
This reframes you as an ally in their success, often unlocking more candid advice.
Interpreting Answers
What references say matters less than how they say it.
Red Flags
| Signal | What It Might Mean |
|---|---|
| Long pause before answering | Considering how to spin something negative |
| "They were fine" / "adequate" | Damning with faint praise |
| Deflects to different topic | Avoiding addressing something |
| "I can only confirm dates" | May have negative information they can't share |
| Lots of qualifiers ("sometimes," "could be") | Inconsistent performance |
| Praises effort over outcomes | Worked hard but didn't deliver |
| "They had strong opinions" | Difficult to work with |
Green Flags
| Signal | What It Means |
|---|---|
| Specific, detailed examples | Reference knows their work well |
| Enthusiasm in voice | Genuine positive feeling |
| "One of the best I've worked with" | Strong endorsement |
| Offers additional context unprompted | Wants you to understand them well |
| Would "absolutely" rehire | Strong signal |
| Asks about the role to give relevant feedback | Engaged, thoughtful reference |
The "Good But Not Great" Signal
Sometimes references reveal a capable but unremarkable performer through pattern of answers:
- "They did good work" (but no standout examples)
- "They were reliable" (but no leadership or initiative examples)
- "They worked well with the team" (but no multiplier effect)
This might be exactly what you need—not every role requires a rockstar. But if you're hiring for senior/staff level, these signals suggest a mismatch.
Beyond Provided References
Provided references are pre-selected and often coached. Additional signals help.
Back-Channel References
People who've worked with the candidate but weren't provided as references offer unfiltered perspective. Find them through LinkedIn connections, mutual contacts, or direct asks: "Is there anyone else who worked closely with them that you'd suggest I speak with?"
Important: Always be professional and discreet. Back-channel references should supplement, not replace, provided references.
Reference Patterns
One reference call is a data point. Multiple calls reveal patterns.
| Pattern | Interpretation |
|---|---|
| Consistent praise across references | Likely accurate signal |
| Consistent concerns across references | Almost certainly accurate |
| Inconsistent feedback | Role-dependent or changed over time |
| All glowing, no development areas | References are coached or superficial |
| Former managers enthusiastic, peers less so | May manage up well but not across |
Reference Check Red Flags
Some situations warrant extra caution:
| Situation | Concern |
|---|---|
| Can't provide any direct manager reference | Why not? |
| Only provides references from one company | Limited perspective |
| All references are peers, no managers | Manager relationship may have been poor |
| Reference seems uncomfortable | Something they can't or won't say |
| Reference contradicts candidate's story | Dishonesty or different perception |
When you encounter red flags, dig deeper. Ask: "Can you help me understand [specific inconsistency]?" Or seek additional references who can provide missing perspective.
What You Can't Ask
Legal and ethical boundaries exist.
Don't ask about:
- Protected class status (age, family status, disability, etc.)
- Salary history (in many jurisdictions)
- Reasons for leaving (beyond what candidate shared)
- Personal life details
Do focus on:
- Job performance and capabilities
- Working style and collaboration
- Professional development areas
- Objective, job-related observations
After the failed hire that started this article, we rebuilt our reference check process. Specific questions, attention to hesitation and nuance, multiple references, back-channels for senior hires. Our reference checks now take twice as long but catch issues that save months of pain later.
References will tell you the truth—if you ask the right questions and listen carefully enough to hear it.
References
[^1]: SmithSpektrum reference check analysis, 300+ engineering hires, 2019-2026. [^2]: SHRM, "Reference Checking Best Practices," 2024. [^3]: Harvard Business Review, "The Reference Check," 2023. [^4]: LinkedIn Talent Solutions, "Reference Check Guide," 2025.
Need help designing your reference check process? Contact SmithSpektrum for templates and training.
Author: Irvan Smith, Founder & Managing Director at SmithSpektrum