Matt Ridley lays them out in this poetical Twitter thread:

If a pandemic caused by a new bat-derived sars-like virus breaks out in a city and
The city has no similar viruses in its local bats and
Has no sars-like antibodies in its people and
Has no infected animals in its markets and
Sars like viruses have leaked at least four times from laboratories and
The city has a laboratory studying bat-borne sars-like viruses and
That laboratory has published more papers on sars-like viruses than any other and
Has the world’s largest collection of bat-borne coronaviruses and
Took its database offline and
This included a sars-like coronavirus very closely related to the pandemic virus and
That virus was collected on one of at least 7 visits to a mine 1885km away by road and
That mine is now off limits to outsiders and heavily guarded and
3 men died after becoming infected at that site from a suspected sars-like infection and
The laboratory has omitted the connection to that outbreak in publications and
It has changed the name of a bat borne virus it collected there and
Has misled the world about when it sequenced the genome of that virus and
Did not publish details of eight other viruses from the same site for 11 months and
Has done experiments to make chimeric sars-like viruses and
Those experiments leave no trace of genetic engineering and
It has tested those chimeric viruses in human airway epithelial cells and
Has tested those chimeric viruses in humanised mice and
It has done these experiments at lower biosafety levels (BSL-2 and BSL-3) and
Has been criticised for poor laboratory safety standards and
Has patented devices for keeping bats in the lab and
Has patented devices for treating bat-bite injuries and
Has previously worked on the insertion of furin cleavage sites into MERS-like coronaviruses and
No other sars-like virus has been found with a S1/S2 furin cleavage site and
The lab has recently applied for grants to insert furin cleavage sites into sars-like viruses and
The government of that country has strongly resisted a full investigation and
Has championed an implausible explanation based on imported frozen food and
Has frustrated the attempts of outsiders to seek relevant information
Then
It is plausible that pandemic may have begun with a lab leak or research-related accident.