This time, it was Melania. The potential first lady delivered a speech Monday night that appeared to have lifted a paragraph from a speech given by Michelle Obama in 2008.

As they’ve done since Trump kicked off his presidential bid a little over a year ago, the Trump campaign played defense by going on offense, using the publicity as an opportunity to attack Hillary Clinton. At this point in time, it’s not immediately clear who, ultimately, is responsible for the error. What is clear is that Trump — both before and after his campaign kicked off last June — has repeatedly attached his name to work that appears to have been plagiarized from other sources.

This past March, as originally reported by The Daily Caller, Trump appeared to blatantly plagiarize an op-ed written by Ben Carson 12 days earlier.

Both op-eds were written on the subject of America’s territories and commonwealths. Carson’s op-ed ran Feb. 26 in the Marianas Variety, a news organization covering the Northern Mariana Islands. Trump’s op-ed ran March 9 in the Pacific News Daily, based in Guam. Entire paragraphs from Carson’s op-ed were inserted verbatim into Trump’s piece.

Compare Trump’s op-ed to the one written by Ben Carson 12 days earlier https://t.co/aUiXlnKLyl pic.twitter.com/0eHE1R4z6Y — Alex Pappas (@AlexPappas) March 16, 2016

Three months prior, Jeb Bush’s campaign accused Trump of plagiarizing Bush’s policy proposals on tax rates and the Department of Veteran Affairs (VA). Bush’s plan, published several month’s before Trump’s, promised to “Modernize the Department of Veterans Affairs.” Trump’s said he would “Modernize the VA.” Bush’s plan focused on “improving practices so that we eliminate billions of dollars in waste, fraud, and abuse.” Trump’s plan said he would “End waste, fraud and abuse at the VA.”

One Bush adviser said that the Trump plan’s promise to “Better support our women veterans” — a hallmark of the Bush plan — was a dead giveaway,” according National Review. To go through all that and come up with a plan that’s 80 percent identical, it’s not an accident,” the adviser said, a sentiment echoed by Bush communications director Tim Miller in comments to National Review. “It’s pretty clear that Trump has been trying to look over Jeb’s shoulder in class to cheat on the test,” Miller said.

Left-wing website The New Republic ran an article just last week accusing Trump of ripping his campaign themes from Richard Nixon. The article pointed to the way Trump is selling himself as the “law and order candidate,” as well as his insistence that the “silent majority” stands with Trump — two themes pushed by Nixon in the late 1960’s. Repeating general campaign themes, however, typically isn’t as great a political sin as passing off someone else’s the speeches or written work as one’s own.

Trump’s apparent plagiarism hasn’t been limited to the political arena.

Last month, the New York Times reported that the Trump Institute — to which Trump gave his name and credibility but did not own — had charged “students” thousands of dollars for lessons using plagiarized textbooks. The textbooks used by the Trump Institute contained at least 20 pages of material ripped from an “obscure real state manual published a decade earlier,” the Times reported. In 2005, Trump appeared in an infomercial for the Trump Institute. “I put all of my concepts that have worked so well for me, new and old, into our seminar,” he said in the video. “I’m teaching what I’ve learned.”

In an interview with radio host Hugh Hewitt last year, Trump took a shot at Vice President Joe Biden for plagiarizing while in law school. “I think I’d match-up great. I’m a job producer,” he said in response to rumors that Biden would seek the Democratic nomination for president.

“I’ve had a great record, I haven’t been involved in plagiarism.”

Follow Peter Hasson on Twitter @PeterJHasson