David G. Friehling, born November 27, 1959, is an American accountant infamous for his complicity in Bernard Madoff's Ponzi scheme, the largest investment fraud in history. As Madoff's long-time external accountant, he operated through his small firm, Friehling & Horowitz CPAs, P.C., in New City, New York, serving as the external auditor for Madoff Investment Securities LLC from the early 1990s until the scheme's collapse in 2008. Despite this role, Friehling failed to conduct meaningful audits, instead rubber-stamping Madoff's fraudulent financial statements submitted to the U.S. Securities and Exchange Commission (SEC), which concealed the ongoing Ponzi operation defrauding investors of billions.

Friehling was arrested on March 2, 2009, and charged with securities fraud, aiding and abetting investment adviser fraud, making false filings with the SEC, and related offenses. On November 23, 2009, he pleaded guilty to seven felony counts, admitting he never verified Madoff's trades or assets and ignored red flags. In a deferred prosecution agreement, he cooperated extensively with authorities. On November 19, 2014, he was sentenced to probation, barred for life from practicing before the SEC, and ordered to forfeit over $2.1 million in fees received from Madoff, avoiding prison time.