Stupidest ever decision by the football authorities
Obviously it's voting Nottingham F****t into the Football League in 1892, for which Notts have to take a fair amount of blame, but there are some others which defy belief.
High flying Peterborough United's punishment in 1967/68: Posh were looking good for promotion to the 2nd tier, they were told in NOVEMBER that they would be relegated for financial breaches, they had to play out the rest of the season knowing that no matter what they did, they would get a points deduction at the end of the season to ensure they finished rock bottom. Incredibly. 4th tier Port Vale were expelled for similar offences that same season, but this was effectively meaningless because they were voted straight back in again and suffered zero consequences. Manchester United also breached the financial rules the following season and were merely fined.
Perhaps worse still, Arsenal in 1914 finished 5th in the 2nd tier. The top flight was expanded after the war allowing for an extra team to be promoted, 3rd place Barnsley could have expected to go up but instead Arsenal went up on a vote due to 'historical achievements'.