Police Scotland Chief Constable Phil Gormley has resigned with immediate effect, the Scottish Police Authority said.
The independent Investigations and Review Commissioner (Pirc) announced they were looking into a fifth allegation of gross misconduct against him last month as he fought for his job amid bullying allegations.
Watchdogs at the Scottish Police Authority (SPA) referred a complaint to investigators, with Commissioner Kate Frame confirming she considered if the allegation was proved it would amount to gross misconduct.
A Pirc spokesman said at the time: ‘The Commissioner has received five misconduct referrals about the Chief Constable from the SPA in the past six months, all of which are currently being investigated.
‘Once each investigation is concluded, the Commissioner will submit a report to the SPA containing a summary of evidence and an opinion on whether the misconduct allegations should be referred to an misconduct hearing.’
Mr Gormley denied all allegations made against him and has been special leave from his post since September.
His wife, Claire Gormley, attacked the justice secretary in January, complaining her husband had been ‘vilified’ in a ‘disproportionate fishing expedition’.