Julia Roberts and Patrick Bergin in 'Sleeping with the Enemy', where Laura (Roberts) fakes her own death to escape from her abusive husband

When Professor Orla Muldoon wants to explain the concept of coercive control to her students, she refers to the 1991 psychological thriller Sleeping With the Enemy.

In the film, Julia Roberts plays Laura, a woman who escapes from a deeply controlling and abusive husband who becomes threatening and even physically violent if she doesn't comply with his wishes - which include a demand that the tins and jars in the kitchen cupboard are lined up in perfect order.

Why did Laura comply with these extreme requests, asks Muldoon, founding professor of the Department of Psychology at the University of Limerick and a director at UL's Centre for Social Issues Research.

Fear, she explains. Although her obsessive husband Martin, played by Patrick Bergin, doesn't hit her every time he finds something out of place, "the threat of violence was there for these small things." So Laura changes her behaviour, explains Muldoon.

"That is what coercive control is," she explains. Fear of another person to such an extent that you will do anything they require:

In a normal relationship, she explains, we all do things for our partners that we'd sooner not bother with, such as attending a tiresome work function. "But you're not doing it out of fear," says Muldoon

With coercive control, however, she says, "it's like always walking on eggshells. You change your behaviour because you see the person as a threat. You're basically afraid of them."

Muldoon welcomes the fact that, in January, under the new Domestic Violence Act 2018, coercive control of another person becomes a criminal offence.

"It's a good thing that coercive control will be recognised in legislation, because it's an important element of an abusive relationship. It erodes peoples' self-esteem," she says.

However, she worries that its existence in a relationship will be "extremely difficult to prove". New research published in the Journal of Family Violence earlier this month demonstrates how even young people growing up in families affected by domestic violence have difficulty recognising the presence of coercive control in the home.

"Young adults report that they only really 'got' it after they witnessed a violent incident at home. If those sitting looking at this behaviour in their sitting room struggle to name it, this may be a very difficult thing to recognise and prosecute," she warns.

Muldoon adds: "If the violence is missing, it will be case of he said/she said - and we know how that goes in rape trials.

"I hope that I'm wrong but I think it will be really hard to prove."

Muldoon adds that she fears convictions for coercive control may only occur in cases where physical violence has been proved, "and then the person will also be found guilty of coercive control".

The damage caused by this form of abuse can be significant, she warns.

"There is lots of evidence, including some that we have collected here in Ireland and published in The Journal of Interpersonal Violence in 2017, that coercive control - using threats of violence or humiliation to control and undermine others - is particularly damaging to the victim's psychological health. Recognition of and recovery from the abuse can be painstakingly slow."

Coercive control can be extremely personally damaging on a number of levels, observes Dr Malie Coyne, a clinical psychologist and lecturer at NUIG who has worked with victims of this kind of abuse.

"Because coercive control doesn't relate to a single incident, but is rather a purposeful and sustained pattern of controlling behaviour where one person seeks to exert power, control or coercion over another in a relationship day in day out, the damage can often be deep and cumulative.

"From an attack on a partner's liberty and human rights, to isolating them from sources of crucial social support, to exploitation of their financial and emotional resources, to depriving them of the means needed for independence and overall well-being - the impact is far-reaching," she observes.

One of the first signs is the erosion of a victim's social network.

"Victims are discouraged from having a social life by low-level, insidious, pernicious statements or questions about a friend or family member," explains Muldoon.

People in a relationship like this can lose their 'sense of self', comments consultant psychiatrist, Professor Veronica O'Keane, a senior lecturer at the Department of Psychiatry in Trinity College, who warns that the subsequent loss of self-esteem and self-confidence can also lead to "a loss of social function," so that a victim may feel incapable of attending a social event or even talking to other people.

Coercive control is often part of the relationship from the outset, explains former director of the National Domestic Violence Intervention Agency and author of two books on coercive control, Don Hennessy. Hennessy, who has worked with victims of this form of abuse for 30 years, says coercive control is usually exerted by a male, who deliberately selects and targets a particular woman.

"When I worked with abusers I discovered that they generally had a plan and a range of tactics that would come into play as soon as they met a 'target woman'.

"In the beginning of the relationship, the woman shares information about what makes her feel good, how she thinks, how she reacts and what her emotional life is like.

"Women tend to talk about these things. This gives him a huge amount of information about her inner world which he then uses to control her.

"The man will listen to the woman and recognise what she is afraid of - for example, a fear of not being a good cook.

"He will work on that so that it gets to the stage that she's terrified of putting a meal in front of him. The extreme end of this will involve physical violence and intimidation. It also involves sexual violence and rape."

From the very beginning, he says, the abuser will establish what Hennessy calls "the terms and conditions" of the relationship.

"A woman will soon learn what she can and cannot do," he explains, like being late for a date or saying something he doesn't like in front of friends.

The woman becomes responsible for the "temperature" of the relationship, and if it's out of kilter, she will assume both the blame, and the responsibility to put things right.

There is generally a lot of "supervision in terms of texts or phone calls" by the abuser, who may want to know where his partner is at all times, Muldoon explains.

She explains that an abuser will often make a point of showing up unexpectedly in places where he shouldn't be. Even though the victim complies with his demands, explains Muldoon, the control will escalate to occasional violence or the threat of violence, even to the family pet.

"Coercive control is ultimately about owning and controlling a person. It's not about love," she warns.

Hennessy has had clients who were never allowed to switch off their mobile phones or who were routinely forced to submit to the humiliation of having their car mileage and grocery receipts checked:

"If he rings and she doesn't answer immediately, there'll be a row," he says, adding that one of the more "sinister" aspects of coercive control is that an abuser will pick something his victim feels good at, such as her sense of style, or her parenting methods.

"She will be bombarded with incessant criticism," he says, adding that this can eat into a person's "soul and spirit".

Hennessy says that in the end, an abuser "silences the woman's natural intuition. He essentially takes over her thinking so that she's entirely caught up in his view of the world to such an extent that she will even use his language - if she's punched with a closed fist, Hennessy explains, she will use his word for it; 'slap'."

Is there a particular type of personality that is vulnerable to this form of abuse? The answer to that, says Professor Muldoon, is another question.

Why, she asks, are we looking to find a particular type of woman - because it is usually women - who are abused, instead of looking for a particular type of man who will do this?

"Girls are socialised into thinking that they are 'somebody' when they are a wife, a partner or a mother," says Muldoon. "Their roles are defined by their relationship with men.

"The person responsible for the abuse is the man. It's not about the woman's personality. It's about the way we position women in terms of their relationship with men - and abusers take advantage of that."

Overcoming coercive control can be difficult, but there is hope, says Hennessy, whose latest book on the phenomenon, Steps to Freedom: Escaping Intimate Abuse was published by The Liberties Press in March, six years after his first, How He Gets into her Head: The Mind of the Male Intimate Abuser .

The first thing a victim must do is to recognise that she or he is being abused through coercive control, says Hennessy.

Next, the victim has to stop telling the abuser things.

"Understand that your openness about your own inner world and your responses to things are giving him the necessary insights on how to control you.

"Don't tell him about yourself anymore. Agree with him. Stop telling him what you're thinking and don't warn him about actions you may take in response to his abusive behaviour."

Next, stop taking the blame for the abuse, counsels Hennessy.

"Understand that you're not responsible for what's happening - but don't say this to him. This must happen internally because if he thinks he's losing control, he'll become more intimidating and physically abusive."

Stop trying to make him a better person, he advises, and start thinking about whether this relationship is good for you.

Start to quietly put yourself first, and do things that you enjoy but that he does not allow. Tell him lies to facilitate this.

"Start listening to your instincts," he advises, and above all, recognise that there is nothing wrong with you other than your need for freedom from this oppression.

Walk away if necessary, counsels Dr Coyne.

"If a relationship is becoming detrimental to your well-being, it's OK to walk away. Some people are simply too toxic to ever be willing to change.

"If someone continually violates your boundaries, end the relationship. Life is too short to spend around people who are hurtful and controlling."

There is hope, says Hennessy.

"Over the 30 years I have worked in this area, I have seen women come out of appalling circumstances and blossom."

Red flags: Coercive control & its effects

* Your social network starts to diminish as you are discouraged from interacting with friends, family members and relatives

* You are responsible for the 'health' of the relationship - and you are to blame if things go wrong

* You're doing things you don't want to do, out of fear of upsetting your partner

* You're not doing things you used to like doing, for fear of upsetting your partner

* You are being 'micro-managed' - your partner wants to know where you are at all times

* You live under the threat of, or may suffer from physical or sexual violence

* You live with incessant criticism which erodes your confidence in yourself and your abilities

The effects on the victim

* Social isolation

* Loss of self-esteem and self-confidence

* Physical and psychological damage

* Loss of status as an independent and capable adult

* Loss of sense of self and personal autonomy

Where to find help

* Safe Ireland

Tel: 090 6479078

Visit: safeireland.ie

Email: info@safeireland.ie

* Women's Aid

National Freephone, Tel: 1800 341 900

Visit: womensaid.ie

Email: helpline@womensaid.ie.

* Rape Crisis Help

Tel: 1800 778888

Visit: rapecrisishelp.ie

Email: info@rcc.ie

* ADAPT Domestic Abuse Services

Tel: 061 412354

Visit: adaptservices.ie

Email: info@adaptservices.ie

Health & Living