Purpose: The purpose of this study is to analyse the role of line management in promoting Diversity, Equity and Inclusion (DEI) in Higher Education Institutions (HEIs). Transformational leadership (TL) promotes DEI, and autocratic leadership curbs it. Design/methodology/approach: The research approach is deductive from existing literature followed by auto ethnographic case study. Findings: The finding of this study is how the autocracy of a line manager can kill the enthusiasm of a team member. Cascuta theory, which has been introduced as a parasitic form of management in paper, will come into existence when a less qualified and closed mindset is supervising a highly qualified and performing team. Research limitations/implications: The research limitations included inadequate autoethnographic case studies on similar circumstances. Also, the literature is divisive over the topic of DEI. On paper, policies are very strong; however, the implementation is not so good in many academic departments at many universities. Here, the whole HEIs is not to blame. Rather, the line manager has a bigger role in acknowledging or rejecting DEI. This research has many implications for studying the Cascuta phenomenon amongst DEI students, DEI staff. Practical implications: The DEI colleagues in some academic departments of many universities in the UK are facing affinity biases. This study could be used to identify and remove the roadblocks in acknowledging the role of DEI in the UK HEIs. These remedies, though, might only be cosmetic. Persons who encourage affinity biases may also be the ones carrying out DEI programmes (Sodhi, 2024). Second, instead of taking concrete action to solve urgent social issues in the workplace, institutions may view DEI activities as regulatory mandates. Social implications: Regional committees could be a good alternative to explore the success of implementing DEI on a wider scale. The members could be from HEIs, who are renowned for their DEI policy implementation. Their implementation process, roadblocks, and wider benefits could be studied on a wider scale. The DEI people should be able to contribute to society with ownership. If they are contributing to the economy, education, or health care, they are an asset and not a burden on society. If HEI is not recognising DEI now, they may find their way out to a more acceptable place. Originality/value: This is a novel study to explore the role of line leadership in promoting DEI in HEI using the deductive method, supported with an autoethnographic case study.