Sourcing, suspicion and speculation -- terminology that has been frequently explored over the last day and a half as Prince Harry testified in a London courtroom in his lawsuit against a major British newspaper publisher over claims of historic phone hacking.

The Duke of Sussex returned to the witness box on Wednesday, for another grueling showdown with the Mirror Group Newspapers (MGN), who he is suing alongside three other claimants representing dozens of celebrities.

His appearance focused on 33 articles -- covering various events over a roughly 15-year period of the duke's life -- published in MGN titles, the Daily Mirror, Sunday Mirror and The People. Prince Harry alleges that the publisher used unlawful methods to produce stories about him and others in his vicinity.

The publisher has denied any illicit acts, with its lawyers arguing that the stories selected to be discussed at trial (out of around 140 articles) could have been sourced through legitimate information gathering means or were already in the public domain. However, MGN has previously admitted and apologized for one instance of unlawful information gathering nearly two decades ago.

Seated once more in the witness box behind several computer monitors where he was able to view documents being methodically picked over, the 38-year-old royal appeared more spirited on Wednesday than a day earlier.

Under the bright lights of the simple court room, the prince largely remained softly spoken but also seemed more confident when responding to questions. At times, he also sparred with Andrew Green, the lawyer representing MGN. The day before he had seemed more measured and took on a more deflective approach with brief, clipped replies.

At one point during Wednesday's proceedings, while Green was quizzing Harry on his time in the Armed Forces and discussing the issue of public interest, the duke responded sternly asking, "Are you suggesting that while I was in the army, everything was available to write about?"

Harry's job in court was to present specific examples of compelling proof to back up his claims that he was a victim of phone hacking. The duke once more recalled being deeply affected by the numerous articles when they were first published but was frequently unable to remember specific dates when pressed by his questioner.

Instead, he often spoke of what would make him suspicious in the tabloid coverage, such as the attribution of quotes to unnamed sources, which would often lead Harry to believe the information had been obtained through the hacking of his cell phone or those of people close to him.

Sources can play a key role in royal reporting. Journalists will go to them for context on a press release, statement, at a royal engagement, or to confirm or disprove rumors. It's a long-accepted practice in the United Kingdom that harks from a time when Buckingham Palace didn't have an official press office. Journalists would use unnamed sources within the institution to find out or clarify what was going on. Prince Harry argued during the trial that some tabloid reporters have used the blanket term of "royal sources" to shield more nefarious practices.

Many observers pored over Prince Harry's courtroom behavior but he kept his cool throughout and failed to reveal any bombshells that might further embarrass his wider family. Though that's not to say there weren't points that were awkward to hear about.

In representing MGN, Green forensically went through the tabloid articles in question in excruciating detail. There were times when we learned more about bust-ups with former girlfriends and club nights out.

During the course of the cross-examination, Green pushed for specifics from Harry for his phone hacking allegations, saying there was "not a single item of call data at any time" between the royal's phone and any Mirror Group journalist. The duke told the court he firmly believed that phone hacking was at an "industrial scale" across "at least three papers," before adding that it would be an "injustice" if his claim was not successful.

The toll of being the first senior royal to testify in court in over 130 years appeared to emotionally push Prince Harry toward the end of proceedings. He seemed to choke up when asked by his lawyer how the cross-examination had been. Answering after a lengthy pause, Harry admitted that "it is a lot."

"For my whole life, the press misled me, covered up the wrongdoing, and sitting here in court knowing that the (respondents have) the evidence in front of them and for (opposition lawyer) Mr. Green to suggest I'm speculating... I'm not sure what to say about that," the duke said.

Harry's cross-examination in his case against MGN is now over. But this is just one of a series of ongoing legal actions the duke is pursuing. For Harry, it isn't just about highlighting the intrusive press coverage he has faced but speaks to his wider years-long mission to reform the media.

Whether he wins the case is for the court to decide but after two days in the witness box, he has once more triggered a conversation about journalistic practices, and he may ultimately succeed in helping changing approaches in the long run.

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