In a warning to anyone bringing cocaine or other illegal substances into parliament, the speaker said he was treating the matter as a priority and wanted to see “full and effective enforcement of the law” with serious sanctions for those flouting the rules.
Sir Lindsay’s move comes after The Sunday Times reported that an investigation found evidence of cocaine in 11 out of 12 locations tested in the building.
One senior MP said it was time to consider bringing in sniffer dogs to detect illicit substances.
The speaker said: “The accounts of drug misuse in Parliament given to the Sunday Times are deeply concerning - and I will be raising them as a priority with the Metropolitan Police next week.
“I expect to see full and effective enforcement of the law.”
Sir Lindsay added: “While parliament provides extensive support services for any staff or members who may need help with drug misuse - and I would encourage anyone struggling with such issues to take up such help – for those who choose to flout the law and bring the institution into disrepute the sanctions are serious.”
Watch: Police seize £78m worth of cocaine from Northamptonshire warehouse
The Sunday Times reported that commons officials had received reports last month that cannabis could be smelt in an open space – often used by staff for cigarette breaks – between two parliamentary buildings housing MPs’ offices and committee rooms.
Cocaine detection wipe tests carried out in a single evening on 12 locations in parliament found evidence of the class A substance in lavatories near the offices of prime minster Boris Johnson and home secretary Priti Patel, as well other washrooms, the paper said.
The newspaper quoted anonymous Westminster sources claiming that drug use was rife among some staff and MPs.
One was quoted as saying: “I have seen an MP openly snorting cocaine at a party. There were journalists present and I warned them that what they were doing was extremely dangerous and they could be exposed but they seemed to get off on the power trip.”
Another said: “MPs tend to be more careful than staff and will go back to their office to do it rather than doing it in any of the public spaces, but I have heard of one staffer who walked in on their MP doing a late-night line at their desk.”
One Westminster veteran told the paper: “There is a cocaine culture in parliament. Some people are at it all the time and are totally blasé. Others dabble. Some are household names, some are ambitious young MPs and officials, but all of them risk throwing away their careers. They think they are untouchable, protected by their friends in the bubble. It’s shocking but also sad. Lots of them need help.”
Sir Lindsay raised concerns about the scale of drug use at Westminster during his campaign to succeed John Bercow as speaker in 2019, telling MPs: “It’s not just drink we’ve got to catch out, there is a drug problem.”
Watch: What does woke mean?
Since then, figures released by the Metropolitan Police under freedom of information laws have shown that there were 17 drug crimes detected in or near the parliamentary buildings in the past year. Police investigated 38 drug offences on the estate between 2015 and 2018.
Conservative MP Charles Walker, who chairs the administration committee, said that the issue would be discussed by the House of Commons Commission next week and sniffer dogs could be brought in.
“The House of Commons has a long history of using sniffer dogs to detect explosives,” he said. “It may be that we now need to broaden the range of sniffer dogs ... to include those which can detect drugs.”
The issue has blown up as Mr Johnson steps up action against drugs, warning middle-class cocaine users they could have their passports or driving licences confiscated if fines prove no deterrent.
He is also expected in the coming week to announce a new clampdown on county lines drug operations moving crack and heroin from England and Wales’s cities into every area of the country.
Jenny Symmons, who chairs the GMB union branch for parliamentary staff, said: “Parliament is a microcosm of the country so of course drugs will be a problem, but the working culture of late nights and short deadlines can create a pressure that feels unmanageable. Support must be available for those who have turned to drugs and we must continue to improve working conditions for staff.”
Jacob Rees-Mogg, the commons leader, said: “The Palace of Westminster ought to be the bastion of lawfulness. There are a lot of police on the parliamentary estate who should enforce the law using all the tools at their disposal to stop drug dealing and drug abuse within the palace.”