A Green frontbencher whose views on transgender rights were behind the decision of Siân Berry to step down as co-leader is to stand for the vacant leadership himself, saying the party should become a beacon to “politically homeless” women. In a candidacy statement that appears likely to reignite a sometimes fractious internal debate about trans rights and the wider issue of the party’s internal structures, Shahrar Ali called for what he termed “a culture of open debate, where the taking of offence is not used as a means to prevent those who do wish to debate from doing so”. He said: “You need a leader not afraid to question, and to actively take a stand against, the abuse directed upon women – many of whom have been driven to resign from parties and others of whom are resisting from within. “I will defend and champion all the protected characteristics enshrined in the Equality Act 2010. This includes the sex-based rights of women and girls, some 52% of the population.” While she did not name Ali, when Berry announced last month that she would not stand again as leader of the Greens in England and Wales her decision was understood to be based on the party’s decision in June to make him spokesperson for policing and domestic safety. Last year, when he was also standing to be the party’s leader, Ali faced criticism from a number of members for tweeting a statement which said women were commonly defined as “an adult human female and, genetically, typified by two XX chromosomes”. Berry, the Greens’ candidate for London mayor, who was co-leader alongside Jonathan Bartley, said there was “an inconsistency between the sincere promise to fight for trans rights and inclusion in my work and the message sent by the party’s choice of frontbench representatives”. Under the party’s decentralised structures, its leaders do not get to select frontbench roles and Berry said she felt that being unable to sway opinion on the issue within the party was “a failure of leadership”. Ali, a former party deputy leader, said: “It’s a very difficult debate to have reasonably, calmly and thoughtfully, and that’s all I’ve ever done and sought to do. “In any arena of equalities, if you’ve got a group of people who feel that they are affected by the claims of another group of people, that requires negotiation. And in order to negotiate you need to debate, and tease out and interrogate other people’s assumptions, if only to work out that there’s misunderstanding. “And I do feel that kind of debate and culture is in increasingly short supply, in society and in political parties.” Ali added that while Berry had not named anyone, he was in no doubt that her comments in resigning were directed at him. Berry and Bartley first won the leadership in 2018, taking over from the previous pairing of Bartley and the party’s sole MP, Caroline Lucas, and were re-elected last year. Bartley is also standing down. Three pairs have already announced their candidacy. One is formed of Amelia Womack, the current deputy leader, alongside Tamsin Omond, who is believed to be the first non-binary person to contest the leadership of a national party. Another pairing is made up of Carla Denyer, a former aide to Lucas, and former deputy leader Adrian Ramsay. Martin Hemingway and Tina Rothery, longstanding environmental activists based in the north of England, make up the final pair.