I think there is levels to this and a public service issue. Also is your role as MP been monetised. If you are a Dr or some other profession that needs to work to maintain your qualifications that should be allowed. No one would have a issue with Cox doing Pro Bona legal work, especially if it was with vulnerable people in his community. It could be said working among the community enhances your ability to be an MP.Exactly - if your MP gets £400k for his/her side hustle and £80k for being your MP which job is really the side hustle? Plenty of their constituents have second jobs though - the reason for that being is to pay the rent or clothe the kids or just to buy food and thats what these MP's don't get as they are so far removed from reality
The issue here is Cox is taking an astronomical sum of money, for a case against the government while been away from his constituents for two months at a time. Added to the fact that he has not spoken in Parliament since February 2020. In the case of Patterson he has directly monetised his role as MP, without it nobody was given him a 100k a year. The argument you could make is Cox's previous Role as AG has allowed him to charge these fees, but ultimately you wonder why he bothers. He seems to have little interest in been an MP or serving the public. Be best to just go back to his legal career.