They might not bother with the computer stuff, but it might depend on the state. Some places still consider weed to be a serious crime, like Oklahoma where you can get life in prison for making hash. If they're willing to put someone in prison for life, they'd be willing to spend a couple thousand to have a company analyze the hard drive. Forensic recovery can be cheap these days. Lots of private companies do this for a relatively small fee, so it's easier than ever for cops (or anyone else) to recover info.