Mercurio, who wrote the hit BBC crime drama, jokingly tweeted his “thanks” to the prime minister for “submitting your audition for the next series of #LineofDuty”, before adding “but we’re looking for a character with at least one redeeming moral principle and a performance that places even just a scintilla of doubt in the audience’s mind that he might not be totally bent”.
The leading screenwriter also included a photo of Mr Johnson wearing a police hat and jacket.
Mr Johnson had been attending a raid linked to Operation Toxic involving officers from the British Transport Police and Merseyside Police in Liverpool on Monday.
One Twitter user described Mercurio’s comments as worthy of winning “Tweet of the year”, while a second said the post was “yet another reason to love Line of Duty and its writer”.
Mr Johnson is under growing pressure to explain what happened in Downing Street last year when a Christmas party was said to have been held during coronavirus restrictions.
The Metropolitan Police has said it was considering complaints submitted by two Labour MPs.
The prime minister was in Liverpool to launch a new 10-year drugs strategy for England and Wales, with government officials likely hoping that a week of announcements on the issue would take the pressure off suggestions the party at No 10 broke Covid rules.
The announcements include a pledge to break up 2,000 “county lines” drug gangs in a £300m drive to rid the country's streets of illegal narcotics.
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