Trump's devoted new press secretary is no different from her predecessors

“I will never lie to you,” declared Kayleigh McEnany on her debut as the White House press secretary at the start of the month. “You have my word on that.”

That would be a welcome change, reasoned critics of Donald Trump, but their hopes of a change in the way his administration communicates have been dashed.

McEnany has stunned viewers with her evangelical devotion to the US president (“who I believe is one of the best presidents, if not the best president, this country will ever have”), her straight-faced defence of his wildest conspiracy theories and her already-wearing-thin stunt of trying to turn the tables on reporters.

Her briefing on Tuesday was, wrote the Washington Post, “a case study in gaslighting, whataboutism and false claims”.

Six times the press secretary was asked about tweets in which Trump promoted a totally debunked conspiracy theory about Joe Scarborough having some role in the death of Lori Klausutis, an aide who served in his office when he was a Republican member of Congress. Now a TV host on MSNBC, Scarborough and Trump spar constantly. Six times McEnany ducked the questions.

Related: Kayleigh McEnany – the 'acceptable' face of Trumpism who infuriates liberals

Klausutis died in 2001 after losing consciousness from an abnormal heart rhythm and hitting her head on a desk. Her widower has asked Twitter to delete Trump’s posts, arguing that he “has taken something that does not belong to him – the memory of my dead wife – and perverted it for perceived political gain”.

Jon Karl, the White House correspondent of ABC News, asked: “Why is the president making these unfounded allegations? This is pretty nuts, isn’t it? The president is accusing somebody of possible murder? The family is pleading with the president to please stop unfounded conspiracy theories. Why is he doing it?”

McEnany studied her binder of notes then sought to deflect by pointing to a 2003 radio programme in which host Don Imus can be heard telling a joke about the death of an intern and Scarborough is heard laughing.

“Well, you know, I would note that the president said this morning that this is not an original Trump thought, and it is not. In fact, in 2003, on Don Imus’s show, it was Don Imus and Joe Scarborough that joked about killing an intern – joked and laughed about it. So that was, I’m sure, pretty hurtful to Lori’s family.”

On Tuesday McEnany was also asked about Trump’s tweets that appeared to mock rival Joe Biden for wearing a face mask at a Memorial Day event on Monday. She gave an odd reply: “It is a bit peculiar though that, in his basement, right next to his wife, he’s not wearing a mask, but he’s wearing one outdoors when he’s socially distanced. So I think that there was a discrepancy there.”

And as at previous briefings, McEnany also recycled mendacious and misleading claims about “Obamagate” and the Russia investigation. “John Brennan, of all of the – I’ll call them bad actors, because indeed they were – of the Obama administration, John Brennan probably has the most to answer,” she said of the former CIA director.

The instant verdict on McEnany was scathing. Joe Lockhart, a former White House press secretary under Bill Clinton, tweeted: “@PressSec entire defense of the President heartlessly causing pain to a Florida family to gain some perceived political position or punish an enemy is to repeatedly talk about an interview that was done in 2003. It is beyond disgraceful and pathetic. Someone come up w/ the word.”

The incident captured growing dismay over the way McEnany, 32, Trump’s fourth press secretary, has approached the position. At first glance, she is cordial with reporters and goes out of her way to include all present in the question and answer sessions. But she also becomes highly combative and has a tendency to end briefings by grilling journalists for not focusing on subjects of her choosing – a move bound to enthrall the Trump base.

Last week, for example, she offered unsolicited advice on what to ask about the case of Trump’s former national security adviser Michael Flynn. “I would like to lay out a series of questions and perhaps, if I write them out in a slide format – maybe we’re visual learners and you guys will follow up with journalistic curiosity,” she said in a tone many found patronising.

In response, Chris Wallace, the host of Fox News Sunday, told viewers this weekend: “I spent six years in the White House briefing room covering Ronald Reagan. I have to say, I never – and in the years since too – I never saw a White House press secretary act like that.”

Wallace added: “Kayleigh McEnany isn’t acting like she’s working for the public. She acts like she is what she used to be, which is a spokesperson for the Trump campaign.”

Appearing on the same show, Jonah Goldberg, the editor-in-chief of The Dispatch website, described McEnany’s behaviour as “indefensible and grotesque”. He added: “What Donald Trump wants in a press secretary is a Twitter troll who goes on attack, doesn’t actually care about doing the job they have and instead wants to impress, really, an audience of one and make another part of official Washington another one of these, essentially, cable news and Twitter laboratory arenas.”

In June 2015, McEnany had condemned Trump as a “showman” but she quickly leaped about the Trump train. May’s briefings suggest she will ride it all the way to the November election.

Kurt Bardella, a political commentator and columnist, said: “We’ve seen that, unsurprisingly, Kayleigh McEnany is treating the job of White House press secretary as being the chief spokesperson for the Trump re-election campaign.