Even the most unsparing critic of the news media cannot deny the tremendous effort put forth by Washington Post reporter David A. Fahrenthold as he spent months doggedly trying to document all of Donald Trump’s donations to charity. The task wasn’t easy—the candidate refused to release his tax returns—so Fahrenthold probed records going back decades, repeatedly questioned the Trump campaign, and contacted more than 400 nonprofit organizations while showing his work.

His thoroughness was a sight to see. For example:

#435. I heard a rumor that @realDonaldTrump donated a pair of pants to this grp. Seriously. I'll keep you updated. pic.twitter.com/JJjdscSoI7 — David Fahrenthold (@Fahrenthold) November 4, 2016

This transparently conducted reporting yielded much information. The public learned that the Donald J. Trump Foundation once spent $20,000 on a portrait of Donald Trump; that $258,000 from his charitable foundation was used to settle legal problems; that he misled the audience of The Celebrity Apprentice about his giving.

Fahrenthold noted in September that “Trump paid a penalty this year to the Internal Revenue Service for a 2013 donation in which the foundation gave $25,000 to a campaign group affiliated with Florida Attorney General Pamela Bondi (R).” In other words, his foundation illegally used money that was supposed to go to charity for politics. And last month, Fahrenthold reported on another instance of the Trump Foundation admitting its misbehavior with its own funds:

President-elect Donald Trump’s charitable foundation has admitted to the Internal Revenue Service that it violated a legal prohibition against “self-dealing,” which bars nonprofit leaders from using their charity’s money to help themselves, their businesses or their families. The admission was contained in the Donald J. Trump Foundation’s IRS tax filings for 2015, which were recently posted online at the nonprofit-tracking site GuideStar. A GuideStar spokesman said the forms were uploaded by the Trump Foundation’s law firm, Morgan, Lewis & Bockius. The Washington Post could not immediately confirm if the same forms had actually been sent to the IRS. In one section of the form, the IRS asked whether the Trump Foundation had transferred “income or assets to a disqualified person.” A disqualified person, in this context, might be Trump — the foundation’s president — or a member of his family or a Trump-owned business. The foundation checked yes. For 2015, the Trump Foundation checked “yes” when asked whether it had transferred “income or assets to a disqualified person” — which in this context might be Trump, a member of his family or a Trump-owned business — and checked “yes” again when asked if it had engaged in any acts of self-dealing in prior years. For 2014, The foundation answered “no” to these questions. Another line on the form asked whether the Trump Foundation had engaged in any acts of self-dealing in prior years. The Trump Foundation checked yes again.

In articles offering an overall look at Trump’s charitable giving, Fahrenthold has explained that the billionaire gave $1 million to a veteran’s group this year after promising he would do so on the campaign trail (but failing to do so until pressed by the media).