SAINT JOHN, N.B. -- The lead investigator of the murder of Richard Oland says he was aware of an allegation that a former officer was asked to alter his testimony about the case, but he didn't do anything about it.

The defence began its cross-examination of Const. Stephen Davidson of the Saint John Police Force on Friday.

Davidson said he met with former Staff Sgt. Mike King on Sept. 8 to drop off documents so King could prepare to testify at the trial.

Last week, King testified that he was asked by former Inspector Glen McCloskey last year, before or during the preliminary hearing, not to tell the court that McCloskey entered the crime scene on July 7, 2011 -- the day that Richard Oland's body was found face down in a pool of blood in his Saint John office.

McCloskey, who is now deputy chief, has denied the allegation.

Defence lawyer Gary Miller asked why Davidson did nothing with the information when King made the same allegation to him.

"You are the lead investigator and you didn't report it," Miller said.

"This is a conversation between him and McCloskey," Davidson replied. "I didn't know what's true."

The defence also went over the interview Davidson conducted with Dennis Oland on the evening his father's body was found.

Dennis Oland, 47, has pleaded not guilty to a charge of second-degree murder.

Miller pointed out that during the videotaped interview, Davidson repeatedly told the younger Oland that he'd be able to verify everything he said with the use of security cameras.

Davidson agreed, and told Miller he didn't know if there were any cameras inside the building at 52 Canterbury Street, but suggested there were, just to see what Oland would say.

"So again he is warned of video surveillance that could trip him up?" Miller said. "Yes," Davidson replied.

During the interview Oland said he wore a navy blazer the previous day, but previous testimony has indicated that Oland was wearing a brown blazer.

Davidson says he didn't get any information on Oland's clothing prior to the interview.

"He became a suspect based on what we saw there (in the video of the interview)? Miller asked.

"Yes," Davidson replied.

Miller also asked Davidson about statements he took from employees of Printing Plus, which is located below Richard Oland's office.

Two employees have testified they heard loud thumps on the floor above, around 7:30 p.m. on July 6, 2011 and based their estimate of the time in relation to a man who stopped into their shop and asked them to send a fax for him. The time stamp on the fax was 8:11 p.m.

Davidson detailed his lengthy but unsuccessful efforts to track the man down.

Earlier, Davidson spent Friday morning testifying for the Crown about cell phone tests conducted as part of the investigation into Richard Oland's death.

Davidson provided details of test calls made with an iPhone similar to Richard Oland's - which hasn't been seen since Oland's death - from various locations in Saint John and Rothesay.

Davidson also testified about test drives he made from Oland's Canterbury Street office to the Renforth Wharf and Dennis Oland's home in Rothesay.

He recorded a variety of travel times based on the routes taken.

The court has heard that Richard Oland died after being struck more than 40 times in the head and neck with a hammer-type instrument and blade-type weapon.