Fake experts are a huge contributor to misinformation online, and they really make it difficult to work out what’s true. It’s much easier to spot red flags for questionable behaviour than to learn a topic yourself and assess the information directly. So inspired by Dr Jess Stokes-Parish’s CRABS framework for assessing credibility of health information, we came up with an acronym for spotting dodgy experts: MUDCAPS.
Think of this as a way to protect your brain from all the “mud” online!
These warning signs aren’t black-and-white. There’s nuance, and in some situations there’s a very valid reason to do these things. But if an “expert” ticks a lot of these boxes, consistently, it’s probably a good idea to take their opinions very lightly.

M = Misleading credentials
Are they trying to trick you into trusting them more? LinkedIn is handy for checking this!
Examples:
- Using a PhD with little relevance to look like an expert in a different area
- Non-medical doctors trying to look like medical doctors (note: DC = chiropractor, ND and NMD = naturopathic doctor)
- Trainee pretending to be fully qualified
- Pretending a diploma or certificate is a degree
- Pretending they went to a fancier university
U = Undisclosed everything
If someone is comfortable bending the truth in some areas, they’ll probably bend the truth in their area of expertise too.
Examples:
- Undisclosed conflicts of interest e.g. if they own a related business (again, LinkedIn is great)
- Lots of image filters
- Not disclosing ads
- Hiding “#ad” or “#spon” or “#brandpartner” at the end of the caption
D = Defensive
If an expert is defensive and hostile when asked (polite) questions, it often means they’re not confident about what they’ve said.
C = Credit
Do they care about giving correct info, and supporting others who do? Or do they want to look smart, and keep all the attention?
Examples:
- Do they say where they got their information, especially if it’s not their area?
- If they’re citing scientific papers, do they have the background to understand them?
- Does it seem like they’re copying someone they didn’t mention?
A = Authority
Overusing appeal to authority – when someone leans really hard on “I’m an expert and that’s why I’m right”, especially when questioned. If they understand a topic properly, they should be able to cite evidence and explain their reasoning.
P = Peers
Do they associate with and promote dodgy people and sources? This is a sign of poor judgement, and lack of responsibility. Expert recommendations are powerful!
Sacrificing their own standards for clout probably means low standards in the info they put out too (shoutout to @medlifecrisis for adding this part!)
Examples:
- Collaborating with a lot of dodgy people
- Following a lot of questionable sources (unless they’re tracking misinformation, for example)
- Promoting dodgy people or products
S = Spotty track record
Everyone has blind spots and makes mistakes, and changing your mind with new info is good. But someone’s long term patterns can be revealing! Check their past posts.
Examples:
- Sharing lots of info you know is incorrect
- Inconsistent opinions (e.g. new favourite product every week)
- Changes their mind too much (maybe they’re saying things they don’t believe, or they don’t factcheck before posting)