I read the news that one of Mark Rothko's Seagram murals (Black on Maroon, 1958) had been vandalised at Tate Modern while I was at its sister gallery, Tate Britain, wandering the Pre-Raphaelite exhibition.

According to a statement released by the museum:

"Tate can confirm that at 15.25 this afternoon there was an incident at Tate Modern in which a visitor defaced one of Rothko's Seagram murals by applying a small area of black paint with a brush to the painting. The police are currently investigating the incident."

My own ideas relating to vandalism and artworks have been in flux over the past few years, moving towards seeing vandalism not necessarily as a good thing but certainly not a disaster.

I've written about the Seagram murals before because they formed part of the massive Rothko show at Tate Modern in 2008. In fact, if the Telegraph coverage is accurate, the painting in question was the one which opened up Rothko's work for me that day; a beautiful and subtle moment of illumination. (I say "if" because checking the picture leading the Telegraph's article against the photo Tim Wright posted to Twitter of the damage it doesn't feel like the same painting to me.)

But as much as I loved the artworks, I don't find myself angry at the act of vandalism per se. The thing which bothers me is the knock on effects of vandalism - the fact that there will be people who are furious and that fury could end up limiting the physical enjoyment of Rothko's work.

According to the Telegraph:

"Questions will be asked about security at the gallery, where the Rothkos are not protected by glass and are separated from visitors only be a low-level barrier that can easily be stepped over.

"Typically, each room is monitored by a single gallery attendant.

"It was Rothko himself who stipulated how his work should be displayed at the Tate."

Essentially, Rothko had a specific vision for this series. I know it included the particular grey colour the walls of the room should be painted and I suspect it extended to the lack of framing and glazing. Rothko knew how he wanted people to experience the work and he was right. As part of that earlier Tate exhibition, one series - Brown and Gray - was exhibited framed and glazed and it actually ruined the experience.

This is what I felt about it at the time:

"The joy and the point of Rothko is the emotional experience which is the culmination of time spent contemplating, even meditating on the work. When you can see the reflections of people coming and going or the outline of some garishly decked out pushchair the illusion is ruined and you are left only with [flat] colours and shapes which (according to the man himself) is the polar opposite of what is supposed to happen. It's only made worse when you get up to leave and realise the colours are distorted by a protective coating on the glass so what you thought was purple is actually gray."

I know that Tate has to deal with things like insurance and lending policies and patrons but I sincerely hope that those concerns don't mean the gallery chooses to limit the experience of any (or indeed all) the Rothkos at Tate.

Speaking more generally, security in a gallery during opening hours is mostly a matter of psychology and the weight of social expectation, buoyed up by the presence of CCTV and attendants saying "don't touch that". For it to be more would require an increase in visitor restrictions and in staffing which, in turn, affects the vitality of the artwork.

I am more than willing to risk the occasional act of vandalism if it means that we can carry on enjoying art at such close quarters.

- Originally featured on Art's In The Right Place

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