A dedicated whistle-blowing policy should be brought into the police service following the death of a senior officer under investigation over claims he sexually harassed women colleagues, a review has found.

David Ainsworth, 49, deputy chief constable of Wiltshire Police, hanged himself in his garage in March last year fearing he would "lose everything" and believing his family would be better off without him if he took his own life.

Lessons must be learned from the "deeply tragic circumstances", a whistle-blowing policy should be brought in and force vetting procedures should be reviewed, a report by Her Majesty's Inspectorate of Constabulary (HMIC) found.

A "dedicated 'whistle-blowing' policy that allows issues to be reviewed in a timely and transparent manner, promoting trust and confidence in the organisation" could help "embed equality and diversity into the core of the organisation and its culture", the report said.

Force vetting procedures should also be reviewed, in particular those policies for chief officers and how they are applied.

"The level of vetting required is determined by the nature of the role and the level of restricted information that is regularly accessed, not the rank of the officer. It should be completed on appointment to a new role that requires a different level of vetting, or at the regular review periods set out in vetting arrangements," the report said.

"There were apparent failures in the operation of the vetting system in Mr Ainsworth's case. As a result of inaction on the part of both Mr Ainsworth and Wiltshire Police, this remained unresolved at the time of Mr Ainsworth's death, a period of 18 months.

"The review team were surprised that both the Chief Constable (Brian
Moore) and police authority had 'assumed' that vetting had been correctly conducted and completed. However, the review found that this is not an issue singular to Wiltshire Police. Senior officers across a number of forces believe that vetting processes occur automatically."

The report's findings will "provide opportunities for a wider audience to review current practice and policy", HMIC said.

It comes after a separate report last week which found that too many officers and staff have taken sexual advantage of members of the public they were supposed to be helping.

More than 50 cases over the last two years show corrupt behaviour by officers which was considered to be sexual exploitation or assault, a joint report by the Independent Police Complaints Commission and Association of Chief Police Officers found.

It called for more vetting of officers in specific situations such as those dealing with vulnerable people, and for a code of conduct to set out the behaviour expected of officers.

Britain's largest trade union Unison, which represented some of the staff who made complaints against Mr Ainsworth, called for more rigorous vetting of senior police officers and a shake-up of whistle-blowing earlier this year.

Mr Ainsworth took his own life following lengthy investigations into allegations of long-standing sexual harassment across two forces, which eventually revealed up to 24 complaints from women.

The £110,000-a-year officer was removed from his duties and later placed on secondment.

Mr Ainsworth was determined to clear his name but felt he was being treated as a "pariah" by the Wiltshire force, the three-day inquest at Trowbridge Town Hall heard in June.

David Ridley, coroner for Wiltshire and Swindon, recorded a verdict that the high-ranking officer took his own life.

Mr Ainsworth's body was found in the garage of the cottage he shared with girlfriend Jo Howes in Potterne, near Devizes, Wiltshire, on March
22 last year.

He left Kent Police, where he served for 22 years, and joined the Wiltshire force in 2008 on promotion to deputy chief constable following the breakdown of his marriage to wife Emma.

The father-of-four was known for his sharp intellect and his ambition was to become a chief constable.

He was shortlisted for the top job with Bedfordshire Police but withdrew in September 2010 when he was told about the misconduct allegations against him.

Mr Ainsworth was removed from frontline duties by Wiltshire's then chief constable Brian Moore, now head of UK Border Force, and put on secondment winding down the disbanded Forensic Science Service in Birmingham.

During the inquest Mr Moore defended the force and said Mr Ainsworth was offered support in the weeks before his death.

A spokesman for Wiltshire Police said: "Today  Her Majesty's Inspectorate of Constabulary (HMIC) have published their 'Lessons Learned Review' on their website.

"The review follows an invitation to HMIC in September 2011 from Wiltshire Police Authority (WPA) and Wiltshire Police. The invitation was to identify any lessons to be learned from the management of issues surrounding the conduct investigation of David Ainsworth.

"We acknowledge that this review was a complex process and HMIC have tried to represent all the contributors' views. However, we are disappointed that, as result of feedback received from staff, it would appear that some of the high level issues, related to senior leadership and recruitment, have not been addressed.

"Through changes we have made internally and 'lessons learned' we will continue to build a progressive organisation where staff treat each other with respect and every staff member feels confident to report wrongdoing.

"We are confident that changes that have been made to our internal policies and strategies address many of the points raised by the review. We use these internal policies to embed a high level of values and professional behaviours in all that we do."