Presuming competence

Also called Presumption of competence, Least dangerous assumption

Start from the assumption that the person understands. If you're wrong, you lose little. If you assume the opposite and you're wrong, you've cost them years.

What it is

Presuming competence means treating a person as someone who understands, thinks, and has something to say, before they have proved it, and especially when they can't prove it in the usual way. You talk to them as you would to anyone their age. You explain what's happening. You offer real vocabulary, not a board with four pictures of snacks.

The idea is often called the least dangerous assumption. Anne Donnellan's argument in 1984 was simple: in the absence of proof either way, choose the assumption that does the least harm if it turns out to be wrong. Assuming understanding and being wrong costs some wasted words. Assuming no understanding and being wrong costs a person their education, their relationships and their voice.

Who it can help

Everyone who can't easily show what they know: non-speaking people, people with profound and multiple learning disabilities, people with dementia, people after a brain injury, people in intensive care. Anybody whose output is limited gets judged on that output, and the judgement is nearly always too low.

It is not a claim that everyone understands everything. It's a starting position, and it's a starting position for the partner, not a diagnosis of the person.

How it works

In practice it changes small things. You speak in full sentences to an adult, not in the sing-song reserved for toddlers. You don't talk about the person over their head as if they weren't there. You give the whole vocabulary, including words the person "probably won't use", because nobody has ever learned a word they weren't given.

It also changes how you read silence. A person who doesn't answer may not have understood; or may have understood, formed an answer, and be unable to get it out in the time you allowed. Wait time exists because the second explanation is far more common than most partners believe.

And it changes assessment. Tests that require speech, pointing or a fast motor response measure output, not understanding. A low score on such a test tells you about the test.

Getting started

Say what's happening before you do it, every time, whether or not you get a reaction. "I'm going to move your chair now." "The doctor's coming at two."

Stop using the words "doesn't understand" and try "hasn't yet shown me". It sounds pedantic and it changes what you do next.

Read the person's communication passport or dictionary if there is one, and if there isn't, start one. The act of writing down what a look or a movement means forces you to notice how much communication is already happening.

Where to get help

Communication Matters puts this principle at the front of its guidance. PMLD Link writes about it for people with the most complex needs. Mencap has plain advice for families and support workers on talking with adults with a learning disability as adults. The Mental Capacity Act starts from the same place in law: a person is assumed to have capacity unless shown otherwise.