Ceon Broughton had a history of giving women drugs and filming them, as well as an interest in images of death, prosecutors believe.

On Thursday Broughton, 30, was found guilty of manslaughter after giving his girlfriend, Louella Fletcher-Michie, a fatal dose of drugs at the Bestival music festival in September 2017.

Footage found on his phone showed him “exhorting [another woman] to take more” of a substance he had given her, while he also took an image of a girlfriend who had injured herself while taking drugs, according to the prosecutor, William Mousley QC.

He sought permission to have the claims presented to the jury at Winchester crown court as evidence during the trial, as he attempted to establish what he said was Broughton’s “pattern of behaviour”.

However, the judge rejected the request, though he came to no conclusion in respect of the credibility of the claims, saying it would do little to assist the jury and that it was too late to introduce evidence fairly.

The footage, which was played in court in the jurors’ absence, showed an unnamed woman sniffing a substance on a spoon held by Broughton. He told her: “No, no, you have to do more.” The woman snorted from the spoon again.

The court also heard that a woman named Paulina Aberg, who lives in Sweden, claimed Broughton photographed her after she fell and banged her head while taking drugs.

Mousley said Aberg found an image of herself on Broughton’s phone, which she deleted.

“She also says over and above that specific incident that she was aware that the defendant had images of people suffering, including suffering death, on his phone in which he appeared to have some interest,” the prosecutor added. He said the potential evidence was “capable of establishing a pattern of behaviour which supported the prosecution case”.

Broughton’s lawyer, Stephen Kamlish QC, said Aberg’s claims about her fall were “not true”. He added: “Whether or not the defendant was with her when it happened, he didn’t know she was hurt because she has to tell him,” Kamlish said.

Kamlish argued the evidence might make the jury think Broughton “took an unhealthy pleasure in Louella’s suffering”, which had “never” been the case.

He said Fletcher-Michie, daughter of the Holby City actor John Michie, had wanted to take drugs at Bestival and Broughton had admitted providing her with some on a previous occasion.

“This has never been the case of the defendant forcing drugs on anyone, they go off to take drugs together because she wants to,” he said.

In a written ruling given to the Press Association, judge Mr Justice Goose said the video clips “offer little, if anything to assist the jury” because the type and supply of the drug being offered was unclear.

The judge added there was “no doubt the deceased wanted to take drugs” at Bestival and Broughton had already admitted supplying drugs to her in June 2017. Goose said Aberg’s statement had come too late to “be fair to the defence”.