Our Team

Marc L. Effron, CPA, JD, CFF, CVA – Managing Partner  (meffron@nullwhiteelmgroup.com)


As a CPA and JD with more than 25 years experience serving client needs in the combined fields of auditing, corporate law and forensic accounting, Mr. Effron has directed or participated in over 250 forensic investigation and dispute matters.  He is experienced in managing complex financial and regulatory investigations ranging from responding to Securities & Exchange Commission, Department of Justice and other regulatory inquiries to small business and matrimonial disputes.

Mr. Effron has also served as a financial consultant, expert, mediator and special master in a variety of litigation matters including post-acquisition, civil monetary, occupational fraud, embezzlement and other disputes.  Mr. Effron is NACVA in Valuation and AICPA Certified in Financial Forensics.

Mr. Effron has served in a variety of leadership roles and was instrumental in developing the audit investigation support protocols for a Big Four accounting firm as well as its Foreign Corrupt Practices Act strategy. Under the investigation support initiative, he was responsible for the development and implementation of the firm’s methodology for confirming the completeness and reliability of forensic investigations performed on the firm’s audit clients.

In his role of supporting law firms and their clients on internal or independent corporate investigations, he has served a multitude of clients with allegations of financial and other irregularities. Clients served include law firms and both public and private entities from a cross section of industries including manufacturing, financial services, logistics, healthcare, technology, real estate, energy and multiple other areas.

Prior to founding White Elm Group, Mr. Effron worked with a public accounting firm and spent 11 years with big four litigation and forensic services units including Ernst & Young and Deloitte.

Prior Roles and Experience Overview

  • Former member of senior management at Big Four accounting firm
  • Former legal adviser (corporate and transactions) for top 25 international law firm


  • Juris Doctor – Northwestern University School of Law
  • Bachelors in Business Administration – Accounting, Emory Goizueta School of Business

Licenses, Awards and Professional Designations

  • CPA – Certified Public Accountant – Georgia
  • JD – Georgia
  • CVA – NACVA Certified Valuation Analyst
  • CFF – Certified in Financial Forensics
  • 40 Under 40 – Recognized by Atlanta Business Chronicle
  • ALM’s Daily Report “Best of” edition – expert witness category


David E. Sems, CPA, CITP, CFF (david@nullwhiteelmgroup.com)

Atlanta and Cleveland


Mr. Sems possesses over 20 years of experience providing forensic technology services to clients in a wide variety of industries. He has extensive familiarity with international work stemming from providing services in 12 countries within Europe and North America – including conducting several 6-8 month investigations in Europe.

Mr. Sems serves as an advisor in the area of forensic technology on the complex forensic technology matters. His skills cover the full range of services from computer forensic analysis to transactional data analytics. He helps clients by finding the “needle in the haystack”. Using leading techniques including fuzzy string matching, link analysis, text mining, computer forensics and cluster analysis.  Mr. Sems leads teams to help clients discover patterns, artifacts and anomalies in huge sets of disparate data that can be used to identify high-risk, non-obvious or suspicious activities.  The results of forensic analysis have helped a multitude of clients and their counsel pursue and achieve recovery in the contexts of theft of trade secrets, restrictive covenant breaches, embezzlement, corporate investigations and other matters.

Mr. Sems is a regular national speaker for various groups including, the Institute of Internal Auditors, the Federal Bureau of Investigation, the Association of Certified Fraud Examiners and the New York Computer Forensic Shows. He also is a guest lecturer at various universities including, Notre Dame, Baldwin-Wallace and Kennesaw State University.

Prior Roles and Experience Overview:

  • Owner/Operator of forensic technology firm, consulting a variety of other firms in the service of their clients
  • Senior Manager experience with a prestigious “Big 4” firm


  • Bachelors of Arts, University of Akron, 1999

Licenses and Professional Designations:

  • Certified Public Accountant – Ohio
  • Certified in Financial Forensics
  • Certified Information Technology Professional


Kevin P. Couillard, ASA, CFA  (Kevin@nullwhiteelmgroup.com)

Mr. Couillard is an affiliate of WEG specializing in business & intangible asset valuation and litigation support regarding valuation/damage matters. His experience includes the valuation of business enterprises, common stock, preferred stock, stock options, general and limited partnership interests, limited liability company interests, debt and note issues, accounts receivable, and other various assets. He has completed valuations for financial reporting, gift and estate tax planning and reporting, state tax planning and reporting, mergers and acquisitions, employee stock ownership plans (ESOP), recapitalizations, management buy-outs, buy-sell agreements, divorce, dissenting shareholders, shareholder disputes, lost profits, and bankruptcy/fraudulent conveyance.

Mr. Couillard’s diversified experience also includes the valuation of intangible assets including patents, trademarks, trade names, proprietary technology, non-competition agreements, assembled work force, going-concern value, goodwill, software, mortgage servicing rights, provider and supplier contracts, and customer lists for various purposes. His experience includes industries such as manufacturing, transportation, wholesale entertainment, healthcare, banking, technology, investment, construction, publishing, real estate, telecommunications, internet domain brokers, and retail.

Kevin is an Accredited Senior Appraiser (ASA) certified in Business Valuation with the American Society of Appraisers and a Chartered Financial Analyst (CFA) with the CFA Institute.  He holds an MBA in Finance from Georgia State University and a Bachelor of Chemical Engineering from the Georgia Institute of Technology.

Prior Roles

  • Experience as working at various regional and
    “Big 4” accounting firms
  • Experience with international textile company
  • Has testimony experience as an expert witness in
    both state and federal jurisdictions


  • Masters of Business Administration in Finance;
    Georgia State University
  • Bachelor of Chemical Engineering; Georgia
    Institute of Technology

Professional Designations

  • ASA – Accredited Senior Appraiser certified in
    Business Valuation with the American Society of Appraisers
  • CFA – Chartered Financial Analyst with the CFA


David J. Kennedy, QSA, CISSP, OSCP, OSCE, GSEC, MCSE, ISO 27001 (Kennedy@nullwhiteelmgroup.com)

David is founder White Elm Group’s affiliates TrustedSec and Binary Defense Systems (BDS).  TrustedSec provides information security consulting services for organizations all around the world. BDS is a global Managed Security Service Provider (MSSP) and software security company which detects attackers in the early stages and prevents large-scale attacks. Prior to TrustedSec and BDS, David was a Chief Security Officer (CSO) for Diebold Incorporated, a Fortune 1000 company located in over 80 countries with over 20,000 employees. David developed a global security program that tackled all aspects of information security. David is considered a forward thinker in the security field and has presented at several hundred conferences worldwide.

David has had the privilege to speak and keynote at some of the nations largest conferences. This includes keynoting Microsoft’s Bluehat, DEF CON, Blackhat, DerbyCon, Grace Hopper, and a number of widely popular conferences. David has had numerous guest appearances on Fox News, CNN, CNBC, MSNBC, Huffington Post, Bloomberg, BBC, The Katie Show, and other high-profile media outlets. In addition, his tools have been featured on a number of TV shows including the History Channel, Mr. Robot, and movies. David has assisted in some of the content for the widely popular Mr. Robot TV show, and advises on other news organizations and TV shows. David is the founder of DerbyCon, a large-scale information security conference.

David has testified in front of Congress on multiple occasions on the threats we face in security and in the government space. David also co-authored Metasploit: The Penetration Testers Guide book, which was number one on Amazon in security for over a year. David was also one of the founding members of the “Penetration Testing Execution Standard (PTES)“. PTES is the industry leading standard and guidelines around how penetration tests should be performed and methodologies which is also now adopted by the Payment Card Industry (PCI) Data Security Standard (DSS) Guidelines for Penetration Testing.

David is also a board of director for the ISC2 organization which is one of the largest security collectives which offers certifications such as the CISSP.

Prior Roles

  • United States Marine Core (USMC) cyber warfare and fornsic analysis
  • 15 years in security over decade specialized in security consulting
  • Creator of open-source tools – The socual Engineer Toolkit (SET), Pentesters Framework (PTF), Artillery, Fast-Track
  • Security advisory releases – Zero Days


  • Malone University
  • Hawaii Pacific University

Professional Designations



Eugene S. Abernathy, CPA (Email)
Eugene Abernathy

Mr. Abernathy has served the accounting profession for over 40 years. He has held leadership roles of several medium to large accounting firms, as well as having extensive leadership experience in “Big 4” accounting firms. His experience includes specializations in auditing, accounting malpractice, inventory valuation, family law, alternative dispute resolution, as well as corporate and individual white collar crime investigations. Mr. Abernathy has significant experience providing his expertise as both an expert and consulting witness on multiple occasions. In his roles as an expert, he has prepared and presented damage calculations related to purchase price disputes, personal injury, employment disputes, lender liability, suretyships, white collar crime and other issues.

In his public accounting career, Mr. Abernathy has worked extensively in the construction and banking industries. In addition, he spent time as the treasurer of one of the United States’ twenty-five largest contractors, giving him practical “hands-on” experience running a business.

Mr. Abernathy has also devoted himself to education. He is a frequent writer and speaker on construction industry accounting and auditing issues. He is a graduate of The University of Georgia, holding a Bachelor of Business Administration with a major in Accounting. He has also completed masters level accounting coursework at Georgia State University in Atlanta, Georgia. Mr. Abernathy has served on numerous committees and panels for The Financial Accounting Standards Board, The American Institute of Certified Public Accountants, The Association of Certified Fraud Examiners, The Georgia Society of CPAs, American Arbitration Association, The Journal of Construction Accounting and Taxation, and the Construction Financial Management Association. Among writing many other high-profile publications, he is a co-author of the American Institute of CPAs’ Construction Industry Audit and Accounting Guide and the landmark Statement of Position 81-1 Accounting for the Performance of Construction-Type and Certain Production-Type Contracts.

Prior Roles and Experience Overview

  • Experience as Director and Managing Director roles at various regional and “Big 4” accounting firms
  • Former Treasurer of one of the United States’ top 25 construction companies
  • Served on the Construction Industry Panel of Arbitrators and Mediators
  • Has testimony experience as an expert witness in both state and federal jurisdiction


  • Bachelor of Business Administration with a major in Accounting, The University of Georgia, 1962
  • Graduate level courses in the Masters of Professional Accountancy Program of Georgia State University. GPA: 4.0

Licenses and Professional Designations

  • Certified Public Accountant – Georgia


Joseph Rubin, CPA, JD (Email)

Mr. Rubin utilizes over 40 years of experience in all financial and management aspects of both publicly traded and privately owned companies. His experience includes assisting clients in real estate transactions (including acquisition, development, operation and sale), business operations and turn around, business planning, accounting and taxes issues, mediation of business disputes, risk management and human resources.

Mr. Rubin’s professional responsibilities have included asset management, development of income-producing properties, purchase of raw land held for investment, and management of shopping centers. He has also successfully overseen the formation of multi-family real estate partnerships and their operation. Mr. Rubin has operated businesses in the following areas: (1) construction of commercial and retail projects; (2) manufacturing of steel products and retail store fixtures; (3) electrical and fire protection contracting; and (4) civil engineering. Mr. Rubin has successfully served in multiple senior officer roles, improving company performance and overall stability.

Mr. Rubin also has experience handling SEC filings (10K, 8K, 10Q, Forms 3, 4 and 5) and investor relations. As a member of senior management of a real estate company, he leveraged his experience with these filings to significantly reduce year-end external auditor fieldwork.
He also has experience negotiating significant company purchases such insurance coverage.

Prior Roles and Experience Overview

  • Former chief executive officer and chief financial officer of a publicly held,
    multi-faceted construction and commercial real estate development company
  • Former chief financial officer of a multi-family real estate company
  • Former chief executive Officer, chief financial officer, and board member of a design, fabrication and installer of material handling systems; design and fabrication of specialty truck bodies and
    accessories; and rail car up fitting and repairs – took that company from a
    seven figure loss in 2005 to a seven figure profit in 2011
  • Has served as a member of boards of directors for multiple construction, real
    estate and manufacturing related companies
  • Former Supervisor at an national tax practice


  • Doctor of Law from the University of North Carolina, Chapel Hill, North Carolina
  • Bachelor of Arts from Guilford College, Greensboro, North Carolina

Licenses and Professional Designations

  • Certified Public Accountant – Georgia
  • Attorney licensed to practice in Georgia
  • Georgia Bar Association
  • Registered Mediator with the State of Georgia


Phillip M. Robertson

Phillip M. Robertson provides consulting services to attorneys, accountants, and other professionals engaged in white-collar fraud litigation; banking and financial institution disputes, business and personal financial disputes, and related training. Mr. Robertson offers expertise in the evaluation of evidence, developing legal strategy, witness evaluation and development, oral and written reports, and interface with law enforcement and regulatory agencies. He develops and presents training in detection, investigation, and prevention of white-collar fraud, insider abuse, and business related disputes. He trains professional groups, regulatory and investigative agencies, and institutions of higher learning.

Mr. Robertson has 41 years’ experience focusing on white collar and financial fraud.
The nature of his investigative experience is wide in scope, including fraud involving liquidation agents and other asset managers, fraudulent reacquisition of property by debtors, criminal avoidance of restitution orders, insider abuse at banks, bank bribery and self-dealing, residential and commercial real estate fraud, criminal non-compliance with regulators, money laundering, frauds involving international asset swaps, looting of institutions through subsidiaries and related parties, fraudulent sales and mergers, embezzlements, self-dealing, hidden interest/bribery, “evergreen loans”, manipulation of accounts and reports, falsification of capital ratios to avoid regulatory scrutiny, back-dating of documents, and schemes to avoid compliance with regulatory directives, consent agreements, and cease and desist orders. In addition, he conducted some of the first United States Secret Service investigations into computer hacking, credit cards, and counterfeit merchandise. He also traveled worldwide with several Presidents and Vice-Presidents of the United States as member of The United States Secret Service.

In the fall of 1999, he led the task force (FDIC, FBI, IRS) investigating and prosecuting the largest bank failure since the Great Depression, and has held multiple regional FDIC investigations supervisor roles, with responsibilities in several major business centers such as New York, Washington, D.C., Atlanta, Kansas City, Dallas, Chicago, and San Francisco.

Mr. Robertson is a regular lecturer for FDIC Commissioned Examiner schools, the Federal Financial Institution Examination Council (FFIEC), and the bi-annual FDIC/Department of Justice Bank

Fraud Conference. He has also spoken at a number of agencies and professional groups, including the Federal Reserve Bank of Philadelphia; both the Arkansas and Alabama State Banking Departments; Ohio Association of CPA’s; Missouri Bankers Association, and Georgia Bar Association. He is a founding member of both the Forensic Accounting Advisory Board and The Center for Forensic Studies in
Accounting and Business, Georgia Southern University.

Prior Roles and Experience Overview

  • Former Special Agent, United States Secret Service
  • Former Regional Investigations Supervisor, United States Federal Deposit Insurance


  • Bachelors of Science in Business Administration, University of Tennessee
  • Graduate of the Southeast School of Banking
Lee N. Katz, CTP (Lee@nullWhiteelmgroup.com)

Lee N. Katz is an affiliate of White Elm Group. Mr. Katz has specialized in turning companies around for more than 30 years. Throughout his career in crisis management, He has served as an interim CEO, CFO or CRO for companies, public and private, with annual revenues from one million dollars up to five billion dollars.

In addition to offering expert-witness testimony regarding business valuations, turnarounds, and plan feasibilities, he has served as a court appointed receiver in multiple states. Mr. Katz’s corporate restructuring and workout experience spans a broad range of industries. He uses his skills to proactively help Boards of Directors prevent crises from happening. He is known for rolling up his sleeves and focusing on the pertinent issues with straightforwardness and integrity.

Mr. Katz is a former Principal at GlassRatner Advisory & Capital Group LLC and the former Chairman and Senior Managing Partner of Grisanti, Galef & Goldress (GGG). Lee been a financial advisor for many receiverships, asset liquidations, and Assignments for the Benefit of Creditors (ABC).

For more than 30 years, Mr. Katz has also been developing and managing commercial real estate for such clients and end users as Wal-Mart, John Wieland Homes, and other private investor groups. He has handled numerous environmental issues for his real estate and corporate manufacturing clients in cooperation with state and national Environmental Protection Agency (EPA) authorities.

Awards & Publications

GGG Partners was recognized, under Mr. Katz’s leadership, by the Turnaround Management Association’s Atlanta Chapter numerous times:

  • 2012 Small Company Turnaround of the Year for Summit Trucking
  • 2011 Large Company Turnaround of the Year for USA Dry Van Logistics
  • 2008 Small Company Turnaround of the Year Benton-Ga, Inc. Learn More
  • 2005 Small Company Turnaround of the Year for Tri-State Delivery, Inc.
  • 2004 Non-Profit Company Turnaround of the Year – Life University Inc. Learn More
  • 2003 Large Company Turnaround of the Year – P.S. Energy Corp.
  • 2002 Large Company Turnaround of the Year – Wyncom Inc. Learn More

Mr. Katz has been featured in the national media, including the following:

  • “It’s Time to Treat America Like a Business,” Atlanta Business Chronicle
  • “What Should the Braves Do?” Atlanta Journal Constitution
  • “Turnaround Magic,” Business to Business Magazine
  • “Squawk Box,” CNBC
  • “Corporate CPR,” The Daily Deal
  • “Turnaround Tycoon,” Atlanta Jewish Times
  • “Living the Lessons,” The Lane Report

Mr. Katz has given more than 100s of presentations throughout the United States to Vistage International and to other CEO and leadership organizations.


  • Bachelor of Science in Industrial Management, Georgia Institute of Technology
  • Bachelor of Laws, John Marshall Law School
  • Licensed Real Estate Broker, State of Georgia


Robert E. Gallagher, CPA, CFE (robert@nullwhiteelmgroup.com)

Bob Gallagher is an affiliate of WEG with nearly 30 years of experience focused on delivering high quality forensic accounting and investigation services. He is a former Big Four partner where he led the firm’s forensic services practice in the Southeast. Bob is a personable and empathetic listener who has a reputation for effectively helping clients meet their objectives and deliver results to their stakeholders. Bob is known for bringing a balanced and objective style to all situations, promoting an environment where people focus on gathering and analyzing information, reaching valid conclusions, and devising optimal action plans.

Bob is an active volunteer with a passion for giving back and making a difference in the community.  He recently founded Gallagher Advisory Services; a firm focused on helping nonprofits fulfill their missions through effective financial management.

Bob’s experience includes:

  • Led many complex internal investigations involving accounting fraud, asset misappropriation, and other types of fraud and regulatory matters. Led teams of forensic accountants, computer forensics specialists, and forensic data analysts in the identification, collection, and analysis of large volumes of complex documents, data and other electronically stored information
  • Extensive experience assisting companies and legal counsel involved in purchase price adjustments, earn-out, and other post-merger disputes. Services included investigating and analyzing proposed adjustments, drafting arbitration briefs supporting the company’s positions, acting as an expert witness or serving as neutral accounting arbitrator/expert.
  • As a big four partner frequently worked with the firm’s audit teams to evaluate clients’ response to allegations of fraud and misconduct including internal investigations conducted by outside counsel and/or forensic accountants.
  • Significant experience in helping multi-national clients develop and implement anti-bribery and corruption compliance programs. His experience includes designing and delivering training, conducting investigations, performing internal audits and compliance assessments, and conducting pre and post-acquisition anti-corruption due diligence. Bob has led such projects in many countries across the globe.

Prior Roles & Experience Overview

  • Partner, Big Four accounting firm, Southeast market forensic services leader
  • Auditor for Big Four firm


  • Bachelor of Arts, Economics – Colby College
  • Master of Science, Professional Accounting – University of Hartford

Licenses and Professional Designations

  • CPA – Certified Public Accountant – Georgia and Massachusetts
  • CFE – Certified Fraud Examiner

White Elm Room

Industry Room

Where to Find Us

Mailing Address:
227 Sandy Springs Place, Suite D362 Atlanta, GA 30328