Previously unseen advice prepared by Nicola Gobbo's police handlers and released on Boxing Day by the Lawyer X royal commission warned that using her as a witness in a high-profile murder case could expose her as a human source, taint high-profile convictions and result in her suing Victoria Police.

The extraordinarily prescient risk analysis prepared by the force's source development unit (SDU) in late 2008 and provided to then deputy commissioner Simon Overland also raised concerns about the defence barrister’s mental health, noting Ms Gobbo was taking morphine daily and was possibly depressed.

Former police commissioner Simon Overland arrives at the royal commission. Credit:Jason South

The protected advice was commissioned by the officer in charge of the SDU, then detective superintendent Anthony Biggin, after learning of a plan by the Petra taskforce investigating the murder of Terence Hodson to take a sworn statement from Ms Gobbo implicating former police detective Paul Dale.

A detailed, strength, weakness, opportunities and threats (SWOT) analysis prepared by one of Ms Gobbo’s SDU handlers said that although Ms Gobbo might have provided critical evidence linking Mr Dale to Hodson's murder, her credibility as a witness would be undermined by her criminal associations and sexual history.