Former England captain Chris Robshaw and his Barbarians team-mates who broke coronavirus protocols will not face a police investigation, London's Metropolitan force announced on Tuesday.
Footage on social media published over the weekend showed a group of players from the invitational side taking part in a drinking session at a pub near the squad's Park Lane hotel.
It was one of two nights out that eventually led to the Barbarians' non-cap international against England at Twickenham on Sunday being cancelled on health grounds.
The decision cost the Rugby Football Union (RFU) an estimated 1 million ($1.3 million) in lost broadcast income and sponsorship revenue.
The video footage shows Robshaw was present with several Barbarians players, including Ireland's Fergus McFadden and Scotland's Sean Maitland.
They appeared to flout several regulations, with England's World Cup-winning coach Clive Woodward criticising the "ridiculously stupid behaviour".
But a police statement said: "The Met will not investigate Covid breaches retrospectively unless they are the most dangerous and flagrant breaches of the regulations.
"The Met is not investigating this incident."
The RFU is still looking into last week's events and the players involved could face disciplinary action.
Cancellation deprived the RFU and stadium workers of much-needed income at a time when the governing body has taken a huge financial hit from Covid-19.
It also scuppered England's plan for a warm-up match ahead of their virus-delayed Six Nations finale away to Italy on Saturday, where victory could be enough to give Eddie Jones's men the title.
The England coach said Robshaw should be spared a torrent of abuse.
"I'm sure if Chris was involved, he'll be sorry for his actions," Jones told Sky Sports on Monday.
"Chris is a good young man. He's served his country well -- let's make sure we don't take it out on him too badly."
Former Harlequins back-rower Robshaw apologised via social media on Friday, saying he had been "irresponsible" and was "sincerely remorseful".