The Tory MP Geoffrey Cox was facing mounting pressure to quit, as Labour referred him to the standards commissioner amid suggestions he used his Commons office for legal work and a senior Conservative figure handed in their resignation over the government’s botched bid to overhaul sleaze rules. After it was revealed the former attorney general moonlighted as a lawyer working for the British Virgin Islands (BVI), Angela Rayner, Labour’s deputy leader, called for an investigation into Cox appearing to use taxpayer-funded parliamentary facilities to appear in a court hearing virtually. She said it was a “brazen breach of the rules”, coming in the wake of disgraced former Tory MP Owen Paterson being found to have committed an “egregious” breach of lobbying rules and holding meetings linked to the two businesses he was paid more than £100,000 in his parliamentary office. Footage of Cox reportedly at a hearing in September showed a background similar to those of MPs’ offices. After it surfaced, Rayner urged the standards commissioner to investigate, and called it “a slap in the face and an insult to British taxpayers”. Some of Cox’s own disgruntled colleagues also vented their fury amid anger at MPs’ second jobs, and Boris Johnson’s spokesperson issued pointed remarks saying all those elected to parliament should be “visible to their constituents”. Cox, 61, declared his extra earnings as a barrister and did not break any rules. But he faced fury for the many hours spent on work unrelated to the Commons and the £150,000 he was paid for giving legal advice to the BVI in relation to corruption charges brought by the UK Foreign Office. He also spent up to a month in the Caribbean tax haven earlier this year but continued to vote in parliament by proxy – a system devised for parliament to continue its work during lockdown. Since being sacked as a minister in a February reshuffle, Cox has spoken in the chamber once. He was revealed to have made £49,154 for 51 hours of legal work for Khan Partnership Solicitors, while he received £14,999 for 14 hours of work for Fidlaw, a business law firm. In the most recent update to the register of MPs’ interests, Cox said he would get an annual salary from 1 November of £400,000 from Withers, the international law firm. About £66,666 would cover this year and he would work for them for 41 hours a month. He registered a total of £970,000 income in the last year, for 705 hours of legal services. Earlier Dominic Raab, the foreign secretary, said Cox’s work overseas was “a legitimate thing to do as long as it’s properly declared” and that it was “quite important” to have “some knowledge of what’s going on” in the BVI. Johnson’s botched bid to overhaul sleaze rules saw Andrew Bowie, a Conservative vice-chair with portfolios for youth and the union, hand in his resignation. Bowie has agreed to stay in the role until a replacement is found. Some newer Tory MPs also rounded on Cox, saying he was “tarnishing the reputation of those of us who don’t have second jobs”. One said “he needs to make a decision as to what he wants to do with his life – either he should do his legal jobs and work wherever that takes him, or be in parliament – he shouldn’t be doing both”. Another said there was an “old guard mentality” to second jobs among veteran MPs in safer seats, and that they were “taking the piss while some of us are solely focused on being a parliamentarian, care about constituents and work hard”. But another Conservative MP claimed Cox’s constituents in the Torridge and West Devon seat he has represented since 2005 were well aware of his work outside parliament, and this had been highlighted on leaflets distributed in the constituency by opposition parties at past elections. Jolyon Maugham QC, who was a tax specialist, said: “I think most of Cox’s constituents would expect him to see their welfare, and that of the communities in Torridge and West Devon, as his main concern. If he isn’t prepared to do that – if he wants to be off arguing cases in tax havens – he shouldn’t be an MP.” Johnson’s spokesperson said it was “incumbent on MPs to be visible, to demonstrate to constituents that they are active on behalf of them”. Asked whether Cox had failed to act in that way, the spokesperson said: “It is up to constituents to make that judgment.” He also confirmed the government would press ahead next week with retracting a motion to overhaul the standards procedure that sparked fury amid the Paterson debacle. The spokesperson said MPs would get a chance on Monday to endorse a standards committee report that detailed Paterson’s breaches of the MPs’ code of conduct. Cox’s office did not respond to a request for comment.