One of the most surprising sentences in Manchester United’s statement on Monday regarding Mason Greenwood’s future was the club’s assertion that their young forward did not carry out the crimes he was charged with.

“Based on the evidence available to us, we have concluded that the material posted online did not provide a full picture and that Mason did not commit the offences in respect of which he was originally charged,” it said.

This is a big commitment for the club to make, especially considering their investigation was conducted by internal staff rather than independently. And when there appear to be so many grey areas regarding what happened.

Richard Arnold, United’s chief executive, admitted in an open letter that the Premier League club had “limited powers of investigation” and were “unable to access certain evidence”.

This article is not designed to suggest Greenwood – who has always denied the charges – is guilty. Or that he is innocent. It instead outlines some of the more complex parts of the case, which perhaps explain why Man United saying he “did not commit the offences” has drawn criticism from supporters and public figures.

The harrowing audio released on social media last January, shortly before Greenwood’s initial arrest, has been widely shared.  A man’s voice can be heard saying: “I asked you politely and you wouldn’t do it (have sex). What else do you want me to do?”

The man also says “move your f***ing legs up” and when the complainant again says she does not want to have sex, the response was chilling: “I don’t give a f**k what you want, you little s**t. I don’t care if you want to have f***ing sex with me. Do you hear me?”

Greenwood has not denied that the male voice on the recording is his. One of the many pieces of advice for women suffering domestic abuse is to record the abuser secretly, using their mobile phone.

In a statement released on Monday, Greenwood accepts he “made mistakes” and takes his “share of responsibility for the situations which led to the social media post”. He also acknowledged that “people will think the worst” because of what “they have seen and heard on social media”.

Arnold said United were provided with “alternative explanations” for the audio clip, which, they say, was a “short excerpt from a much longer recording”.

United say the social media posts were made in the early hours of January 30 last year, after Greenwood had fallen out with the complainant. The picture this paints is that the complainant sought revenge on him.

While nobody other than the complainant can truly know why a decision was made to post the material on social media, the fact it was accompanied by a caption making clear she wanted everyone to know what Greenwood had done raises questions.

The video appears to show a woman with a bloodied face, and bruises on her arms and legs. During their investigation, United concluded there were explanations for the materials posted online and that they were content that Greenwood did not physically abuse the complainant. When these findings were presented to the complainant’s family, United claim they were not contested.

Although United say the complainant was approached by the police rather than initiating contact herself, she gave them an “achieving best evidence” interview in January last year. Three months later, she then provided a retraction statement.

This, however, does not detract from the fact that there was, at least to begin with, a willingness to participate and give her account. United say they went to considerable lengths during their investigation to understand what happened between Greenwood and the complainant.

The complainant did not engage with the club directly. However, her mother did so, with her knowledge. The club say they gave both the complainant and her mother the opportunity to comment on or to correct their investigation’s findings and they did not do so.

Based on their engagement with the mother, United say they are satisfied the complainant was not subject to coercive control by Greenwood. United also concluded that Greenwood did not physically abuse the complainant after being provided with explanations for the materials posted online.

The club have not specified which part of the investigation these explanations came from – merely adding that they were not contested by the complainant’s family.

Gary Neville, a former United player and now a leading TV football pundit, called the club’s process “horrible” and believes an independent panel should have been used to investigate the allegations instead.

Arnold felt that Greenwood was not guilty of the charges he initially faced. However, Arnold is not a lawyer, nor is he a judge, so his legal judgement may raise questions and has been criticised.

“The statement that was put out proclaimed someone innocent from a position that they didn’t have any authority to do,“ UK TV presenter and United supporter, Rachel Riley said on the News Agents podcast.

“I think it’s gaslighting for people to have two statements saying… Mason Greenwood himself saying he’s been cleared of all charges, which is not the case – the claims were dropped because the key witness dropped out. It puts wind in the sails of people who think they can get away with abuse everywhere. And I think for victims, it’s a slap in the face.”

There is an acceptance in the statement that Greenwood made “mistakes” – but what does that mean? No further explanation was given. Patrick Stewart, United’s chief legal officer and general counsel, was part of the executive panel that led their Greenwood investigation.

Although Arnold harboured a certain view, Greater Manchester Police and the UK’s Crown Prosecution Service (CPS) don’t appear to have agreed with him.

The police believed it was necessary to open an investigation and talk to the complainant and to Greenwood. He was arrested on January 31 last year on suspicion of rape and assault, and further arrested the next day on suspicion of sexual assault and making threats to kill.

United say Greenwood co-operated fully with the investigation and handed over the relevant passwords so the contents of his phone could be examined. Instead of concluding there was no case to answer and that this was all a big misunderstanding, the police passed the evidence they had gathered to the CPS.

The CPS reviewed that evidence and, in October, after deciding there was enough of a case to proceed to trial, decided to charge Greenwood with one count of attempted rape, one count of controlling and coercive behaviour and one count of assault occasioning actual bodily harm.

In February this year, those charges were dropped following the withdrawal of key witnesses and new evidence coming to light. At that time, a CPS spokesperson said:

“There was no longer a realistic prospect of conviction. In these circumstances, we are under a duty to stop the case. We would always encourage any potential victims to come forward and report to police and we will prosecute wherever our legal test is met.”

United say the social media posts represent only a small fraction of the evidence considered by the CPS and that, due to the complainant’s right to lifelong anonymity, the new evidence that came to light will not be made public.

• The Athletic report