Over the past few decades, there has been a radical reasasessment of the roles, purposes and responsibilities of museums. No longer primarily inwardly focused on the stewardship of their collections, they are increasingly expected to look at the needs of visitors and communities through a range of educational and other services.

More recently, there has been a growing interest in the potential for museums to be agents of social change, deploying their collections and other resources to contribute towards a more equitable society.

Museums have been required to develop goals that respond to local and global social concerns; articulate and justify their value in social terms; demonstrate and measure their impact; and develop new working practices to reflect these trends.

Several factors have contributed to this reorientation of role and purpose and the widespread conception of museums as agencies with the potential to promote cross-cultural understanding and respect.

These include the growing global influence of human rights debates; the changing demographic composition of many western societies; the 'new social movements' that have led to a proliferation of previously marginalised voices; heightened international interest in cultural diversity and an approach to the politics of difference that rejects assimilationist policies in favour of those that affirm cultural and ethnic differences; and the introduction of increased demands for accountability that have required publicly funded institutions to demonstrate their value to society.

Some priorities for the reshaping of museum roles and responsibilities have been galvanised by government policy. In the UK, the influence of government policy has been especially pronounced.

In 2000, the Department for Culture, Media and Sport issued its policy guidance on publicly funded museums, galleries and archives in England, making the government's expectations that the cultural sector should play a part in combating social exclusion explicit.

The formulation of policies that require museums to contribute to the government's broader social objectives has frequently generated fierce debates around the instrumentalisation of culture.

Although these debates that surround the intrinsic, economic and social value of culture and the nature of the relationships between arts institutions and the state are important, they have often tended to over-simplify the arguments on both sides and obscure some of the more fundamental questions surrounding the purposes and responsibilities of cultural organisations.

While government intervention has often played a significant role in shaping museum policy, it would be inaccurate to suggest new approaches to more inclusive museum practice have evolved only in response to locally framed government policies.

Indeed, in some contexts, museums have pursued social goals that are out of step with the dominant priorities and position of government.

CONTEMPORARY EXPECTATIONS, PRACTICES AND DEBATES

In response to these wide-ranging influences, museums have been increasingly expected to reform and revise their approaches to representing diverse groups.

They have been required to accommodate the interests of many different communities to ensure that exhibitions portray cultural differences in more respectful and equitable ways and to shape their displays through consultation and engagement with the people whose lives are being interpreted.

These demands have translated into a series of questions that have challenged practitioners and continue to frame debates about museums' social role.

How can museums hope to represent all sections of society when group identities are increasingly conceived, not as singular and fixed, but rather as multiple and shifting? Which forms of difference are deemed authentic, valid and thereby privileged over others for inclusion, while others are left aside? Are there universal moral frameworks that should inform responses to these questions and, if so, should they take precedence over local norms of acceptability and tolerance?

Significant shifts in museum practice can be seen in response to these demands, expectations and questions. Over a period of many years, displays which - viewed from a modern perspective - have been perceived to be overtly racist have been revised or dismantled.

In their place, more inclusive and equitable approaches to exhibition development have emerged, as previously marginalised communities - especially women, minority ethnic communities and indigenous peoples - have questioned their exclusion from (or misrepresentation within) museum displays.

These changes in display practice have often been accompanied by strategies to broaden the people who visit museums and the staff who work in them to more accurately reflect the local communities. Although widespread, the extent to which these changes have masked a deeper resistance to a more radical rethinking of notions of cultural and national heritage remains open to debate.

Although some museums are committed to developing new approaches to representation and interpretation, and to engaging audiences in debates about difference, human rights and equality, others continue to produce displays and pursue practices that are perhaps more likely to enhance rather than combat prejudice.

While progress has been made to represent some previously marginalised communities in more respectful and equitable ways, other social groups remain neglected. For example, researchers have highlighted the paucity of exhibitions that include material relating to sexual minorities and the under-representation of disabled people within museum displays.

The fierce and often unhelpfully polarised debates surrounding the recent reorientation of museums' roles, purposes and responsibilities have tended to dwell on two principal questions. The first concerns the capacity that museums have to reinvent themselves as agents of empowering social change.

At one end of the spectrum are those who hold that museums, by definition, cannot change and are increasingly socially irrelevant. At the other end are those who argue that it is unhelpful to view museums as necessarily complicit in maintaining inequitable relations of power.

They acknowledge the history of museums and the part they have played in excluding and marginalising social groups, but highlight several factors that have contributed to change.

The second and arguably more controversial question concerns the extent to which cultural institutions should be enlisted to effect social change. On the one hand are those who argue that museums should be free to pursue their 'core business' autonomously - preserving, documenting, displaying and studying cultural and natural heritage - in isolation from contemporary social or political concerns.

On the other are those who argue that museums have an obligation to deploy their activities in ways that respond to, and seek to influence, societal values.

Situated between these polarised opinions, many practitioners remain ambivalent about the social roles and responsibilities of museums.

This ambivalence is, for some, based on unease with the self aggrandising character of claims that museums can 'change society'. For others, uncertainty is fuelled by an awareness of the problematic moral dilemmas and pitfalls bound up in attempts to deploy museums as agents of social change.

Although the idea of museums being able to reform the way differences are viewed is widely supported, little is known about how this might be achieved. While claims that museums can confront and counter prejudices, engender support for human rights and promote respect between communities have grown increasingly confident and explicit, there remains a paucity of evidence and understanding with which to support these assertions.

It is now thought audiences do not simply absorb messages, but are capable of constructing their own meanings that may radically differ from those intended at the point of production. Research has highlighted the potential for 'misunderstandings' where messages are resisted and turned around by audiences in ways that result in opposite meanings.

Current thinking within museum studies and, in particular, approaches to museum learning that are based on constructivist theories, might also be seen to challenge assumptions that museums can - or should attempt to - combat prejudice through creating change in visitor attitudes and values.

Constructivist exhibitions, as George Hein has argued, 'present a range of points of view and enable visitors to connect with objects through activities and experiences that utilise their life experiences'.

Such approaches encourage and facilitate open-ended learning outcomes and are critical of more didactic approaches, which sanction a limited range of responses and meanings created by the visitor. It might then be argued that constructivist explanations of the ways in which visitors learn, challenge museums seeking to engender non-prejudiced values and attitudes among visitors where alternative, oppositional readings of exhibitions (ones which reinforce or reproduce prejudice) are inevitably viewed as invalid, even aberrant.

AUDIENCE RESPONSES TO ANTI-PREJUDICE MESSAGES

In museum contexts, despite the ubiquity and increasing confidence of claims regarding the role of museums in enhancing understanding, tolerance and respect for difference, there has been surprisingly limited research directed towards investigating the ways in which audiences respond to exhibitions developed with these aims in mind.

An early and rare study highlights many of the challenges inherent in attempts to investigate the role of museums in combating prejudice. In January 1953, an exhibition of Japanese art opened in Washington DC and toured to museums in New York, Seattle, Chicago and finally Boston.

The exhibition was sent to the US by the Japanese government with two aims: 'To acquaint the American people with the cultural and spiritual values and traditions of Japan, and to help, in some fashion, to bring a sympathetic understanding of the Japanese.'

A large-scale study of the 'effectiveness' of the project in achieving its aims was undertaken at three of the museums. The study employed a range of research methods to elicit information about reactions to the exhibition and to investigate the 'effects' of the visit on opinions and attitudes relating to Japan and Japanese people.

Publishing their findings in 1956, Robert Bower and Laure Sharp concluded that 'by and large, the exhibit did not appear quickly to convert large numbers of Americans to a pro-Japanese attitude'.

More recent discussions of the potential for museum exhibitions to influence audience perceptions of difference similarly suggest the potential for apparently 'aberrant', 'deviant' or oppositional constructions of meaning such as those found in the 1950s studies.

An exhibition at Nottingham Castle Museum and Art Gallery in 2000 declared its intentions in an introductory panel in the words of the artist, Alison Lapper: 'My work reflects and responds to other people's attitudes to me. I hope to question and change society's attitudes about physical beauty, normality, disability and sexuality.

'As a disabled person, I am generally perceived as ugly, sexless, inert, helpless and miserable. I know I am not. My work gives me the opportunity to represent myself to the world on my own terms.'

Despite the nature of the exhibition's aims, one visitor's letter of complaint illustrates the potential for the construction of oppositional meanings. She wrote: 'We were particularly offended by the display of photographs of a disabled woman and her baby, which I can only compare to the old "freak show". I know we live in an age of "political correctness" but I do not think that the castle was the place to display such items of so-called modern art.'

While these brief examples offer little conclusive evidence, they nevertheless raise questions about museums' ability to combat prejudice and highlight the need for further, in-depth investigations.

SHAPING THE UNPREDICTABLE

What then are the implications of these findings for an investigation of museums' roles in tackling prejudice? If individual visitors are understood to generate their own highly personalised and variable meanings from the same exhibition encounter, what role, if any, might museums play in facilitating the generation of meanings that counter, rather than reinforce, prejudice?

Despite the variability and unpredictability that has often been found in audience responses to various media, there is nevertheless both theoretical support and empirical evidence to suggest a degree of influence on the part of cultural producers.

CULTURAL AUTHORITY VERSUS READER RESISTANCE

Media theorists argue that audiences are increasingly beset by a potentially bewildering array of messages that compete for their attention. These messages are differentially perceived by audiences. Some are noticed, taken up and used, while others are ignored or discarded. This suggests that we must also consider the specific and unique properties that museums, in comparison with other forms of media, might bring to the communicative process.

In particular, might the museum's status as an authoritative knowledge-provider lend weight to the argument that museums have an especially significant role to play in combating prejudice?

Sharon Macdonald's research at the Science Museum in London provides evidence to support the view that museum exhibitions are often read in ways that reflect their perceived cultural authority. Many visitors came with an expectation that the museum would give 'clear-cut "right answers"'. Moreover, the cultural authority of the museum - its capacity to determine and authoritatively communicate meaning - is evolving.

New approaches to framing exhibitions (for example, the use of interpretive devices that attempt to reveal to visitors the 'constructedness' and inevitable partiality of displays, and the deployment of techniques, which explicitly co-opt visitors into a shared process of establishing meaning), are transforming museum-visitor relations and creating new forms of authority.

It is fair to say there is a degree of tension between the notion of the active or resistant audience (an analysis that gives primacy to the agency of the visitor in constructing meaning) and the conception of the museum as an authoritative and trustworthy knowledge-provider (a view that might suggest audiences defer to the museum in determining meaning).

My interest is in exploring the potential for museums to deploy their cultural status and authority to frame society's conversations about difference in ways that privilege a particular and unequivocal moral standpoint - one based on concepts of social justice.

The suggestion that museums might adopt and attempt to generate support for a particular (non-negotiable) moral position is unfashionable in contemporary museological practice.

In recent years, there has been growing support for the replacement of the authoritative curatorial voice with diverse perspectives, a strategy designed to enable visitors to see that the decisions and judgements made by exhibition makers are open to interpretation and debate.

Of course, such an approach still involves a process of selection, as some viewpoints are deemed appropriate and given voice through their inclusion within the museum, while others are silenced through their omission.

While acknowledging the value of presenting plural perspectives, this interpretive strategy also enables museums to avoid taking a stand on controversial issues and thereby potentially constrains their capacity to challenge prejudices.

In other words, by including different viewpoints but failing to arbitrate between them, museums imply that they are of equal value, an implication, which in some instances, might be undesirable.

Richard Sandell is the deputy head of the department of museum studies at the University of Leicester

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