strange results

Good Morning All,

I have a report which is fired from a procedure. The parameter is @StartDate and i'm getting the exact values until July4th, from July 5th going forward when i click , i'm getting all the records instead of the selected date. 

Any idea where should i start looking into?

I have the following where clause in my SP

where convert(date,rs.[StartDate]) = convert(date,(@StartDate))

Thanks