Three gay friends are considering legal action against Transport for London (TfL) after they say the company failed to properly investigate an incident in which they claim they were subjected to homophobic abuse by a member of tube staff.

The men, all in their mid-twenties, say that while travelling on the underground on the evening of June 26th this year, one of them was punched in the face by a fellow passenger in a homophobic attack.

They said they exited the tube at Finsbury Park station and told a member of staff about the attack, who responded: “What do you expect you f**king poofs?”

The men – a software engineer, customer service worker and a designer – reported the incident to TfL and the police, who subsequently arrested a 38-year-old man. However, the case was dropped due to ‘insufficient evidence’, despite the fact that the altercation was captured on CCTV footage.

TfL, which is number 13 in the Stonewall’s Equality Index – a list of the country’s most gay-friendly companies – has said that staff member cannot be prosecuted unless there is an independent witness, because data protection laws prohibit them from listening to the sound from CCTV recordings.

A spokesperson for TfL said: “TfL takes its obligations under the Data Protection Act 1998 very seriously and must ensure that our CCTV operations adhere to the Information Commissioner’s CCTV Code of Practice, which states that CCTV must not be used to record conversations as this is highly intrusive and unlikely to be justified.”

He added: “This incident was reported to the British Transport Police (BTP) who have since investigated the incident. The BTP consulted with the Crown Prosecution Service who decided no further action should be taken due to insufficient evidence.”

“London Underground strives to provide excellent customer service for our passengers. We take any allegations made against our staff very seriously. All our frontline station staff receive equality and inclusion training. We also pride ourselves in having a workforce that reflects London’s diverse population.

“We are unable to comment on specific incidents, however we take any allegations made against our staff very seriously. We have very strict procedures and training in place to ensure our employees treat all our customers equally.

“When allegations against our staff have been made, these are thoroughly addressed. The managers of that employee will carry out an in depth interview with that individual and carefully look at all evidence available which includes examining CCTV footage.”

Ben Cooke, one of the men in the party, said: “We were very upset by the incident. First, my partner was punched and then we received intimidation from a member of tube staff. It was awful.

“He tried to goad others around the station to harass us too and we felt genuinely scared.

“Lots of hate crime happens where there might not be any evidence. But this happened in an open tube station with plenty of CCTV, yet it seems as though it was completely pointless.

“We spent hours that night speaking to the British Transport Police, then to the station manager, then the next day and over the following week to various officers only to have this thrown back at us. We are now considering legal action,” added Mr Cooke.

Samantha Mangwana, a solicitor at discrimination law firm Russell Jones & Walker, said the friends were likely to have a case for “unlawful victimisation”.

She explained: “It is against the law for businesses to allow their staff to subject service users to homophobic abuse or any act of harassment related to sexual orientation that violates their dignity or creates an intimidating, hostile, degrading, humiliating or offensive atmosphere for them.

“If customers who have tried to take action to enforce these rights then experience further detriments at the hands of the service provider for doing so, such as a failure to take reasonable steps to investigate evidence available to them, that constitutes unlawful victimisation.

“These are not new laws, but they have just this month been confirmed in a new piece of legislation, the Equality Act 2010. Although the new law is not clear about a business’ responsibility for harassment of service users by third parties, it makes it perfectly clear that there is no defence for service providers who tolerate homophobic abuse of customers by their own staff.”