Internal emails are shedding light on jurisdictional disputes between the Winnipeg Police Service and the head of Manitoba's police watchdog.

The Independent Investigation Unit is responsible for probing alleged criminal activity involving police officers, but emails show the agency's director has raised concerns with the chief of police about barriers getting in the way of the investigative process.

The emails which have been released under the Freedom of Information and Protection of Privacy Act illustrate tension between the head of the IIU Zane Tessler and Danny Smyth, chief of the Winnipeg Police Service.

The documents came to light through a Winnipeg Free Press investigation.

In a March 2016 email to former chief of police Devon Clunis, Tessler wrote, "I am concerned that there may be internal criminal investigations of WPS members that are not brought to the attention of the IIU, as required by law."

In March 2017 Tessler wrote to Smyth about an incident under IIU investigation -- in the email he said, “When the subject officer was answering questions posed to him, he openly admitted that he had discussed the shooting incident with other witness officers prior to his interview with IIU investigators.”

Tessler goes on to say police officers should be segregated until investigators have completed their work.

The head of the IIU wasn't available for an on-camera interview Wednesday but a spokesperson said in a statement to CTV News, “While there may be occasional differences of opinion with a police agency, and issues the IIU works to resolve on a case-by-case basis, the unit is fulfilling the mandate prescribed to it under legislation. The IIU has completed approximately 80 investigations.”

Manitoba Justice Minister Cliff Cullen said the government will undertake a review of all aspects of the province’s Police Services Act which governs the IIU.

"We want to make sure that we have an effective process there, we want to make sure that Manitobans are comfortable with that process and it is effective,” said Cullen.

Smyth wasn’t available for an on-camera interview but he said in an emailed statement to CTV News any difficulties would be resolved during the mandatory review being done by the province.

"The bulk of the Police Services Act came into force in June 2012, with the IIU provisions coming into force in June 2015,” said Smyth. “During that time I have had discussions with the director of the IIU regarding the application of the act, specifically their jurisdiction in certain areas.”

“I welcome the pending review required by the act in order that any difficulties we have had arising from our respective positions, as well as others unforeseen, can be resolved."

The IIU said it does recognize there was a learning curve for police agencies when the office first became operational in 2015.

A spokesperson said the number of notifications from Winnipeg police to the IIU has continued to grow which it says indicates the service is becoming more aware of its obligations.