I am a recent graduate of Oxford University, and still live in the city. The other day, visiting a friend’s office to pick up a key in Harris Manchester College, I subsequently couldn’t find anyone with a fob to let me out of the buildings. So I went to the office’s kitchen and worked on my book until the morning, then headed out through the junior common room, chatting briefly with staff and students I knew on the way. Being in someone else’s college isn’t particularly unusual in Oxford, and students are often in the rooms or offices of friends unaccompanied.

Later that day I was shocked to discover that a CCTV image of myself walking around the college had been emailed to all of its staff and students, along with a message warning them to “be vigilant” and “alert member of staff [...] or call Oxford security services” if they see me. The college’s “wonderful and safe environment” can be taken advantage of, it told them, adding that its security officers “do not know [my] intentions” although, as they could also see from the images, “previous interactions had been amenable”.

I was shocked. Had friends and colleagues at Harris Manchester not quickly condemned the email, this criminalised image of me could still be at the forefront of students’ minds. The college bursar told the university news website The Tab that someone had reported seeing a person entering a room at 11:30 the night before. But students were quick to point out that other “unauthorised persons in college” had never had a CCTV image sent around the entire mailing list questioning their intentions. I’m unaware of it happening at any other Oxford college either.

So why, you may be asking, had this happened to me? Was I an “intruder”; or was I was a young black man with locks, who therefore had to be seen as a “suspect”? I wouldn’t be surprised if it was the latter. In my undergraduate Oxford years, studying politics, philosophy and economics, I had experienced several incidences of racial bias and exclusion: markers who didn’t seem to believe that African philosophy was philosophy; being stopped by college porters on the way to tutorials (it happened so much I ended up writing a song about it); members of my college chanting “We are regents, Rhodes must stand” at me (knowing my involvement in organising the Rhodes Must Fall campaign); or having All Souls College call the police when I peacefully protested against their monument to a slave owner.

These incidents are part of a worrying trend. Black and minority students often feel as though they are treated differently by porters and staff. An Iraqi friend of mine reported being IDed by his college while his two white guests, neither of whom had studied at Oxford, were not. Last year a Rhodes scholar at Christ Church recounted being asked, along with two Kenyan friends, “if they were construction workers”. This is also compounded by the staggering under-representation of black students. When pressed by actor David Harewood in a recent BBC documentary, the university said this disparity “did not warrant an institutional response”.

During my time there, there were more old Etonian undergraduates at the university than black students.

But the college security’s actions also tie into the broader criminalisation of black men in British society. In the media we are portrayed as gangsters and thugs. In some areas of the UK we are 17 times more likely to be stopped and searched than white people. We make up 3% of the population yet 14% of the prison population. We are under-represented in higher education and over-represented in unemployment statistics and mental health institutions.

Too often people seem to shrug at these facts, seeming to think they merely show that black people are inherently lazy, or stupid, or lawless. My experience shows the opposite – that black people studying at the highest levels can still be treated as criminals.