Company lists · Data refreshed September 2026

Top 25 Workplace investigation consultants based in the United States

RevenueBase identified 427 workplace investigation consultants headquartered in the United States as of September 2026 and tracks 1,896 professional contacts across them, including 539 with verified work emails. Los Angeles is the largest hub.

This list covers workplace investigation consultants headquartered in the United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 22, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 22, 2026 86% judged on-target in blind review
427Companies
1,896Contacts tracked
539Verified emails
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The 25 largest workplace investigation consultants based in the United States

Ranked by team size
Top 25 of 427 workplace investigation consultants based in the United States, ranked by team size, largest first. Data refreshed Sep 22, 2026. RevenueBase Smart Search rates how each company's information relates to workplace investigation consultants: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Partial evidenceNew York, NY, United StatesHQ checked Sep 22, 202651-200129 contacts →

Partial evidence

“Beau Dietl & Associates is a premier private investigation firm based in New York City with offices in New Jersey, Florida, and California.”

Source: RevenueBase Database · checked Sep 22, 2026
2Indirect evidenceUnited StatesHQ checked Sep 22, 2026201-50094 contacts →

Indirect evidence

“Why Becker & Company?”

Source: RevenueBase Database · checked Sep 22, 2026
3Partial evidenceMonaca, PA, United StatesHQ checked Sep 22, 2026201-50069 contacts →

Partial evidence

“CSI is a full-service investigative firm that delivers key facts to give our clients an actionable advantage in a wide range of situations.”

Source: RevenueBase Database · checked Sep 22, 2026
4Partial evidenceWashington, DC, United StatesHQ checked Sep 22, 202611-5066 contacts →

Partial evidence

Investigative Group International (IGI) is the premier investigative firm conducting independent, high-touch investigations worldwide.”

Source: RevenueBase Database · checked Sep 22, 2026
5Partial evidenceSacramento, CA, United StatesHQ checked Sep 22, 202651-20057 contacts →

Partial evidence

“Today’s professionals rely on investigative firms to help manage risk by detecting and preempting problem situations.”

Source: RevenueBase Database · checked Sep 22, 2026
6Partial evidenceNew York, NY, United StatesHQ checked Sep 22, 202651-20042 contacts →

Partial evidence

“Hilton Global Associates is a professional investigative research firm providing expert due diligence and unparalleled client service.”

Source: RevenueBase Database · checked Sep 22, 2026
7Strong evidenceSacramento, CA, United StatesHQ checked Sep 22, 202611-5041 contacts →

Strong evidence

Workplace investigations provide employers with an effective tool to make informed employment decisions.”

Source: RevenueBase Database · checked Sep 22, 2026
8Indirect evidenceTemecula, CA, United StatesHQ checked Sep 22, 202651-20039 contacts →

Indirect evidence

“Hodson P.I.”

Source: RevenueBase Database · checked Sep 22, 2026
9Strong evidenceSpokane Valley, WA, United StatesHQ checked Sep 22, 202611-5031 contacts →

Strong evidence

“Our mission at Pinnacle Investigations is to provide accurate, timely, compliant background reports to aid our clients in building a safe, secure workplace.”

Source: RevenueBase Database · checked Sep 22, 2026
10Partial evidenceDallas, TX, United StatesHQ checked Sep 22, 202611-5030 contacts →

Partial evidence

“Different by Design: Transforming Workplace Risk into Workplace Trust Workplace misconduct isn’t just disruptive-it creates risk, drains resources, and burdens internal teams with…”

Source: RevenueBase Database · checked Sep 22, 2026
11Strong evidenceAkron, OH, United StatesHQ checked Sep 22, 202611-5028 contacts →

Strong evidence

“SACS Consulting & Investigative Services helps businesses, schools, and non-profits reduce workplace risk through HR support, investigations, security services, and training.”

Source: RevenueBase Database · checked Sep 22, 2026
12Strong evidenceLos Angeles, United StatesHQ checked Sep 22, 202651-20028 contacts →

Strong evidence

“Palicon Group is a Southern California based firm specializing in workplace investigations, security, and public safety consulting.”

Source: RevenueBase Database · checked Sep 22, 2026
13Partial evidenceOakland, CA, United StatesHQ checked Sep 22, 202611-5025 contacts →

Partial evidence

“Oppenheimer Investigations Group LLP focuses on performing timely, fair and thorough investigations of allegations of harassment, discrimination and other misconduct in the…”

Source: RevenueBase Database · checked Sep 22, 2026
14Partial evidenceVacaville, CA, United StatesHQ checked Sep 22, 20261-1022 contacts →

Partial evidence

“A full service private investigation firm specializing in workers' compensation, liability, insurance, and Human Resource solutions.”

Source: RevenueBase Database · checked Sep 22, 2026
15Partial evidenceGreenwood Village, CO, United StatesHQ checked Sep 22, 202611-5017 contacts →

Partial evidence

“When workplace challenges demand expertise you can trust, organizations turn to The AR Group, LLC.”

Source: RevenueBase Database · checked Sep 22, 2026
16Partial evidenceWilmington, DE, United StatesHQ checked Sep 22, 20261,001-5,00012 contacts →

Partial evidence

“Freeh Group International Solutions, LLC (“FGIS”) has been acquired by AlixPartners, LLP, the global management consulting firm, expanding its world-class investigations practice.”

Source: RevenueBase Database · checked Sep 22, 2026
17Indirect evidencePhoenix, AZ, United StatesHQ checked Sep 22, 202651-20012 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 22, 2026
18Indirect evidenceNew York, NY, United StatesHQ checked Sep 22, 20261-1011 contacts →

Indirect evidence

“The team at EPT Legal, LLC has been serving the New York area for decades.”

Source: RevenueBase Database · checked Sep 22, 2026
19Strong evidenceDenver, CO, United StatesHQ checked Sep 22, 202611-5011 contacts →

Strong evidence

“Providing expert workplace and Title IX investigations, strategic HR advice, and compliance training to companies, public entities, and nonprofits since 1995.”

Source: RevenueBase Database · checked Sep 22, 2026
20Strong evidenceLos Angeles, CA, United StatesHQ checked Sep 22, 202611-5010 contacts →

Strong evidence

“Public Interest Investigations is a leading provider of neutral, trauma-informed workplace investigations, Title IX investigations, and criminal investigations for public…”

Source: RevenueBase Database · checked Sep 22, 2026
21Indirect evidenceAtlanta, AL, United StatesHQ checked Sep 22, 20261-1010 contacts →

Indirect evidence

“Information Collection and Risk Mitigation Experts.”

Source: RevenueBase Database · checked Sep 22, 2026
22Partial evidencePinellas Park, FL, United StatesHQ checked Sep 22, 202611-509 contacts →

Partial evidence

“When searching for investigative services, experience will always be a primary concern.”

Source: RevenueBase Database · checked Sep 22, 2026
23Partial evidenceLaguna Niguel, CA, United StatesHQ checked Sep 22, 202611-509 contacts →

Partial evidence

“At the JL Group, we are battle-tested through years of investigative experience.”

Source: RevenueBase Database · checked Sep 22, 2026
24Partial evidenceHouston, TX, United StatesHQ checked Sep 22, 202611-509 contacts →

Partial evidence

“Swailes & Company is a licensed investigative and security consulting company headquartered in Houston, Texas.”

Source: RevenueBase Database · checked Sep 22, 2026
25Partial evidenceSacramento, CA, United StatesHQ checked Sep 22, 20261-109 contacts →

Partial evidence

“Ellis Investigations Law Corporation is a law firm committed to investigating and resolving the most complex issues at work and on campus.”

Source: RevenueBase Database · checked Sep 22, 2026

Showing 25 of 427 workplace investigation consultants based in the United States

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Workplace investigation consultants based in the United States at a glance

As of Sep 22, 2026
28.4%Verified-email coverage
4.4Average contacts per company
1-10Median size (employees)
2.1%Largest-city concentration · Los Angeles
Sep 22, 2026Page data refreshed

Companies by employee count

1-10
343
11-50
66
51-200
13
201-500
4
1,001-5,000
1

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 427 companies.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among workplace investigation consultants, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies
Companies headquartered in the United States whose own description of what they do matches “workplace investigation consultants”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search
RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names workplace investigation consultants), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude
Companies whose own description does not clearly place them among workplace investigation consultants, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
Match quality
In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
Ranking
Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification
Every listed company carries at least one verified work email, 539 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh
This page's figures were pulled from the company graph on September 22, 2026. Lists refresh periodically as the graph is re-checked.
Corrections
Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names workplace investigation consultants, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many workplace investigation consultants are there based in the United States?

RevenueBase identified 427 workplace investigation consultants headquartered in the United States as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Beau Dietl & Associates, headquartered in New York, tops this list with the largest team on record.

Which city has the most workplace investigation consultants?

Los Angeles leads with 9 headquartered companies, followed by Denver (8) and Chicago (7).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 539 verified decision-maker contacts tracked across these 427 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 22, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.