A Conservative MP who has been told to apologise in the Commons for acting in "threatening and intimidating" manner towards parliamentary committee staff said he was under "great pressure" at the time - in part because he is so tall.
The Independent Expert Panel, which determines appeals and sanctions in bullying cases, said the incident in question happened in April 2020 when Daniel Kawczynski was unable to join a committee hearing due to technical issues.
At the time, Parliament was adapting to new remote working arrangements during the first COVID-19 lockdown.
The panel's disciplinary report said the Shrewsbury and Atcham MP had consumed a "significant amount of alcohol" on the day and phoned the manager of the committee staff while under the influence, behaviour that was "grossly unprofessional".
According to the panel, Mr Kawczynski accepted that on several occasions he let the two complainants, referred to as C1 and C2, and others know of his dissatisfaction.
He said that his frustration, combined with more "long-standing personal issues", may have had a "detrimental impact on the way in which he behaved".
According to the panel, Mr Kawczynski told them that he was dealing with a number of "real pressures" in his role as an MP, as well as being under pressure "in part for personal reasons".
"Brexit and serious flooding in his constituency both gave rise to serious difficulties for him as the local MP," the panel said.
"The Respondent is 6'9" tall and thus very conspicuous in the street, in his local shops.
"He found himself under repeated attack by members of the public on both these grounds.
"He emphasised to us how such attacks could be extremely vicious.
"Against that background, the advent of the pandemic added another layer of pressure.
"It was in that context that his frustration with the technical problems associated with a remote meeting caused him to be so angry.
"Nevertheless, he emphasised that he had never set out to bully anyone and did not wish to bully anyone."
The IEP said Mr Kawczynski had apologised to the complainants, but added "some concerns remain as to the sincerity of the apologies given to date".
It added that he should make a public apology in front of MPs.
Chairman Sir Stephen Irwin said: "We accept that the circumstances which arose on April 27 2020 were difficult.
"But they were difficult for everyone. Whilst we fully grasp that the life of an MP can be highly pressurised, these responsibilities and stresses do not justify a loss of courtesy, an exaggerated sense of importance or entitlement, or bullying.
"Our conclusion is that the determination of a requirement to make a public apology on the floor of the House is proper and proportionate."
Kathryn Stone, the Parliamentary Commissioner for Standards, ruled that Mr Kawczynski had acted in an "intimidatory and threatening manner" towards C1 and C2 and "abused his power" by making malicious claims about their poor performance.
The MP had been "repeatedly rude, aggressive and impatient" with the two staff members and other staff, as well as making "critical and untruthful comments" on a WhatsApp group shared with other members of the committee.
C1 lodged a complaint about Mr Kawczynski's behaviour in "several" phone calls and WhatsApp messages.
C2 made a similar complaint, saying that his actions left them feeling "anxious, upset, harassed and intimidated".
The panel was told that the MP used "extreme, although not profane" language when he made a number of calls to C2, with the calls including remarks such as "this is a farce" and "you are useless".
Mr Kawczynski threatened to lodge a formal complaint and referred to C2 as a member of the "snowflake generation", the IEP's report stated.
In an interview with BBC Radio Shropshire, the MP played down the incident in question, saying "we all have bad days".
He added: "But in exasperation at the end of the day I sent a message on the WhatsApp group to my fellow MPs on the committee, and the clerks are also on the communal WhatsApp group and I said 'I'm terribly sorry but I still haven't been able to log on all day, I feel badly let down by the clerks and I'm going to resign from the committee'.
"That has resulted in a 15-month investigation into me by the House of Commons."
Mr Kawczynski said he had "no alternative but to apologise".
"I must apologise because if I don't apologise then I risk the option of being sanctioned further - namely being suspended from the House of Commons or expelled from the House of Commons," he said.
A Conservative Party spokesman said: "The Conservative Party does not tolerate bullying.
"The chief whip has spoken to Dan Kawczynski MP about the standards expected of him.
"Mr Kawczynski has apologised for his actions and will publicly apologise later today."