Evidence is now done in an historic sexual assault trial in Windsor, but a judge must decide if the charges should be stayed.

The lawyer for John Thomas Wuschenny wants five charges stayed because of "unacceptable negligence" on the part of police.

This is a crime that dates back to 1990, but Wuschenny wasn't charged until 2016, after his DNA was found on a shirt.

His lawyer wants the charges dropped because he says the chain of custody for that shirt isn't clear.

A Windsor police officer is the last witness to testify in the trial.

Wuschenny, 57, has pleaded not guilty to sexual assault, forcible confinement, break and enter, disguising himself and threatening death, after a woman told police she was assaulted in her home on Marentette Avenue in 1990.

Const. Barb Everyingham testified she was the first officer to see the woman and took her statement at hospital. But Everingham doesn't know who seized the woman’s shirt, or when.

All she recalls is the clothes were taken at the time of a rape kit by nurses and she handed all the evidence over to an investigator.

That evidence was logged onto what's called an evidence control sheet, but the sheet is now missing.

Wuschennys' defence lawyer argued Monday his clients right to put forward a defence is impaired by lack of evidence.

Andrew Telford-Keogh said they don't know who seized the shirt and where it was stored between 1990 and 2016, when DNA on the shirt was tested again and led to Wuschenny's arrest.

But Crown attorney Walter Costa said due to human nature, some things get lost and he added if they could explain the missing sheet, they could probably find it.

Regardless Costa argued it doesn't change the fact Wuschenny's DNA was found on the shirt and neither he nor the victim had a previous relationship before the alleged assault.

Justice Renee Pomerance says she will have a decision on the charter application on June 15.

If she sides with the defence, the trial 28 years after the alleged crime, is over.

But if Pomerance rejects it, both lawyers say they will be ready to argue final submissions for Wuschenny on all five offences.