The decision to cancel an event with the former home secretary Amber Rudd at Oxford University has been misunderstood as “no-platforming” and is not a free-speech issue, the ethnic diversity representative at the Oxford Feminist Society has said.

The event, In Conversation: Amber Rudd, was organised by UNWomen Oxford as part of its 2020 Trailblazer Series in the lead-up to International Women’s Day on Sunday, but was cancelled 30 minutes before it was due to start after a majority vote by the group’s committee after criticism from students.

The incident shows no signs of blowing over. Oxford University has stated its opposition to “no-platforming” and declared it would ensure there would be no repeat of this situation. Meanwhile, the education secretary, Gavin Williamson, said on Friday evening that the government would step in if universities failed to “defend free speech”.

But Safa Sadozai‎, from the Oxford Feminist Society, drew a distinction between the event – advertised as a celebration of Rudd’s achievements for women, without mentioning the Windrush scandal – and a debate where views were challenged robustly.

“All the promotional material spoke about Rudd’s role in encouraging women to get involved in parliament and the UN,” Sadozai‎ said. “Under that context, it didn’t sound like it could ever be an open debate where views are challenged.”

She said it was widely accepted the decision was last-minute, but described the invitation as “misjudged” and criticised the response of the university.

“It’s been misunderstood by the university as a free-speech issue or no-platforming,” Sadozai said. “Many people here were saying she is not entitled to be celebrated or upheld as a feminist.”

According to the official Facebook listing for the event, the conversation was expected to be premised around the former minister for women and equalities’ work in a traditionally male-dominated field.

The listing said that Rudd had championed equality, urged tough legal penalties to eradicate female genital mutilation and called for a higher proportion of women in cabinet. Rudd has also chaired a cross-party inquiry into unplanned pregnancies, which called for statutory sex and relationships education in all secondary schools, the UNWomen Oxford society said.

But Sadozai said: “I personally don’t think she has been very inspiring, but it depends how other women want to perceive her..

“For an event like International Women’s Day, which is about solidarity, it can’t be that difficult to find someone who has had less of a controversial career. It felt like they were disregarding her role in the Windrush scandal.”

Rudd stepped down as home secretary as the Windrush scandal escalated and it emerged she had misled parliament over the existence of targets within the Home Office to deport undocumented migrants.

The former Tory MP, who stood down at the last election, said the decision to “no-platform” her shortly before the event “to encourage young women into politics” was badly judged. “They should stop hiding and start engaging. #FreeSpeech,” she tweeted on Friday.

Lord MacDonald, the warden of Oxford’s Wadham College, said attendees would have had the opportunity to challenge Rudd on her record and that a free exchange of ideas was fundamental to university life.

“It was made clear by this society in advance that people would be free to question her about her policies in government and the impact they had on women of all races,” he told BBC Radio 4’s Today programme.

“The University of Oxford has a very robust free-speech policy, which acknowledges that a part of free expression is a willingness to be confronted with views that you might find unsettling, extreme or even offensive.”

Last month, historian Prof Selina Todd was forced to pull out of an event after a boycott threat from other speakers. Williamson said it was “unacceptable” for two speakers to have been “no-platformed at Oxford within a week”.

“It is not enough to adopt free-speech codes if they are not enforced,” he told the Telegraph. “I expect the University of Oxford to take robust action over these incidents – and, if universities are not prepared to defend free speech, the government will.”