Fame and sexual exploitation - new research reveals how to spot a sexually exploitative man no matter how famous, respected or 'safe' he appears.

The media is buzzing with rumour as to whether certain household names had been guilty of sexually abusing the young. Some predators seek fame precisely because it creates opportunities to sexually exploit the vulnerable.

Superstars may be protected from detection for many reasons. But the cases being speculated about appear to have got away with the abuse (if the allegations are true) over decades. Is it possible to detect the sexually exploitative earlier? Various TV documentaries may broadcast accusations and confessions, but if there is a mass of evidence available now - why were signs not picked up before?

Psychological theory predicts that sexually exploitative men may actually be very different than commonly imagined. Also the sort of scheming uncovered by recent research suggests these psychologically astute predators will gravitate towards vulnerable populations, such as the young, isolated, immature, naive and intellectually unsophisticated. Under this kind of cover, perpetrators remain undetected for years.

New psychological research just published in the academic journal 'Personality and Individual Differences' has investigated those aspects of male personality which might predict sexually exploitative strategies towards women.

Professor David Buss, David Lewis and colleagues from the University of Texas, who conducted the investigation, argue evolutionary selection pressure over generations means this type could appear on the outside agreeable and charming. If their personality immediately signalled danger to potential victims, no one would place themselves at risk with these perpetrators, and their strategy would be doomed to fail. Given early detection of sexual abuse or exploitation leads to ostracism and other penalties, successful sexual exploiters might be those who put up a clever and believable front.

In another study, also involving Professor Buss, aspects of bodily appearance indicating physical weakness in a woman, were predicted to indicate to men sexual exploitability, but in the end, the study found men were more vigilant for psychological characteristics in women which betrayed vulnerability to sexual misuse. Physical strength proved irrelevant in the male assessment, suggesting those possibly prone to sexual exploitation may be more interested in psychology and manipulation, than sheer physical force.

The University of Texas psychologists, David Lewis, Judith Easton, Cari Goetz and David Buss asked over seventy men aged between 18-47 years old, to examine pictures of different women in a variety of social contexts, displaying an array of emotions, and dressed in varying attire in contrasting situations and poses. Questions posed to the men included, ''How easy would it be for a man to seduce this woman into engaging in sexual intercourse?'' The next two questions used the same wording, but ''seduce'' was replaced in the second and third questions, respectively, with ''pressure'' and ''deceive''. The fourth question asked, ''How easy would it be for a man to sexually assault this woman?''

Previous research has found that women find it more difficult to detect 'worth' in a male mate because for them 'high quality' has more to do with inner characteristics such as intelligence, ambition, honesty and kindness. Because these are more on the 'inside' and not on display on the 'outside', then women struggle for external markers of 'value' and often therefore seize on whether the man is actually in a relationship. Married men are often found more attractive because some other woman, in choosing that man, gives him the feminine stamp of quality approval. Another way of putting this is; women will often ask suspiciously, 'if he's so great, how come he's single?'

What the study entitled 'Exploitative male mating strategies: Personality, mating orientation, and relationship status' reveals, is that women may have been making an error in assuming a man already in a relationship, makes him less likely to be sexually exploitative. In this study being in a relationship was not by itself strongly and purely associated with a less sexually exploitative outlook.

Men who were in relationships and who were more sexually exploitative, scored lower in agreeableness and therefore empathy. Lower empathy contributes to pursuit of sex despite a women's desires. Low agreeableness is also associated with higher 'hostile masculinity' which is basically an individual's predilection for sexual aggression.

Psychologists Cari Goetz, Judith Easton, David Lewis and David Buss have examined what these sexually exploitative men are looking for in women, that will encourage them to attempt sexual exploitation, in a separate study.

The investigation entitled 'Sexual exploitability: observable cues and their link to sexual attraction', found men were alert to certain psychological characteristics in potential female victims. Shyness was one, and previous research has found low self-esteem and low assertiveness are linked in women to suffering sexual coercion.

The study has just recently been published in the academic journal 'Evolution and Human Behaviour', and demonstrated how calculating and psychologically sophisticated, sexually exploitative men may be.

For example, one category of female psychological characteristics these men took as signals that sexual exploitation might be more possible, are cues indicating recklessness or risk taking. Impulsivity, attention seeking, being prone to take risks, are all part of this cluster of traits, and do not in themselves indicate a woman is currently exploitable. However they do signal a greater likelihood she will eventually land in more dangerous predicaments, such as being alone or intoxicated.

Cues suggesting incapacitation in the form of intoxication, fatigue, or other forms of cognitive impairment render a woman less able to resist tactics of sexual exploitation and are signals sexually exploitative men seem to be looking for.

Generally speaking, women are more fussy than men when it comes to finding a partner, and that is partly because they tend to embrace longer term relationships, but this means that if a man comes along with those difficult to find qualities, she is more likely to be lured in, relaxing her usual vigilance.

This is precisely when she is at her most vulnerable.

So, unfortunately the take home message from the latest psychological research appears to be more careful, not less, with the man who boasts external badges of trustworthiness.